Author's Note: This, like "Blood Shadow," is one of my side projects that will update sporadically as I have time away from my main storyline to add to it.

This is a story with male Human/female Sangheili romance. It was written in response to a challenge by a reader who has noticed that the majority of interspecies fanfics are about male Sangheili and female Humans. So, for everyone who wants to see chicks with mandibles, this is for you. On the other hand, if you are saying "ick, ick, ICK" right now, you'll probably want to go read something else.

Rules of Engagement

Chapter the First

Major Evan Doucette had not considered himself the ambassadorial type. He was a career ODST, not a politician, and it had rocked his world when his higher-ups had told him that they had selected him to be Earth's very first ambassador to Sanghelios.

Evan was young for a major, but in a war as bloody as the recently concluded battle with the Covenant, people got promoted very quickly. Thirty years old, with sandy brown hair and the sort of muscular physique that just came with a job as demanding as jumping out of spaceships for a living, Evan had spent his entire adult life serving his planet and his species as a soldier in the UNSC. Now Evan found himself aboard the Covenant…no, the Sangheili ship Boundless Grace, bound for the planet of Sanghelios.

Evan knew he would be returning to Earth at some point in the future, but he had no idea when. He had not thought he would miss it: he had served on Reach and Chi Rho and aboard the UNSC cruiser Make My Day; all of these were more his home than Earth was. And he had no family left on Earth, or anywhere else. But somehow, the knowledge that he was about to leave Human-held space to live in an alien civilization had him already missing the familiar sights and sounds of…

…no, not just Earth. Of humanity.

He was not entirely alone—there were some other Humans on the ship with him, all volunteers, travelling to Sanghelios to serve as his support staff—but they were all going to be living a long way from Human civilization. The Sangheili were Humanity's allies now, but alliance was not the same as friendship, and it was definitely not enough to make an outsider belong.

The Sangheili recognized this simple fact as much as he did. He had been assigned a pair of Sangheili bodyguards, Relu 'Chavam and Lor'n 'Malach, to protect him from Sangheili who might still be bitter about their long years of warfare against Humans, or nursing xenophobic grievances against a "lesser" species like Humanity. Every member of his team had a pair of Sangheili guards as well, but his had the most impressive credentials: Lor'n was a decorated veteran and former member of the Lights of Sanghelios honour guard, while Relu was previously the Captain of the Guard of the old and wealthy Chavam Keep. Evan liked to think that he could protect himself, but he had to admit, he felt a lot better at the prospect of facing Sangheili assassins with Lorn's energy sword and Relu's battle staff beside him.

The Arbiter had also tasked a retired Sangheili, a former warrior, to be his advisor. Lak 'Vadam was an older Sangheili, allegedly a relative of the Arbiter. Lak had been meeting with Evan on a daily basis in the hopes of smoothing over possible difficulties in advance of Evan's arrival on Sanghelios.

In past meetings, Lak and Evan had discussed everything from air conditioning (the temperature in Iruiru could get hot enough to give a human heat stroke for most of the year, and there would be months when Evan would need to stay indoors where it would be cool) to Sangheili cultural taboos to public holidays. Yesterday there had been a long discussion about Evan's diet. Sangheili were obligate carnivores, consuming far more meat than a human would need, and getting their other nutrients through consumption of organs. Evan was not particularly thrilled at the idea of eating a stomach and its contents, so arrangements were made to import Earth plants and teach Sangheili to grow and prepare human vegetables. Evan imagined that he and his people would be eating a lot of field rations in the meantime.

Slowly, Evan realized that choosing a military survivalist might have been a wise decision. Sanghelios was not going to be like a posting to Africa or South America; he could not count on having staff that would know how to wash his clothes, or make his meals, or provide other personal services. The Sangheili would learn in time how to welcome a human guest, but there would be a learning period.

Thankfully, he had Lak to help him.

"Good day, Lak," Evan said with a smile as he walked into the room, where Lak was already seated on a stuffed chair near a coffee table. He'd come to view the senior Sangheili as a sort of grandfather figure. "What's the multiculturalism lesson today?"

Lak fiddled with his fingers, an unusual gesture for the Elite who usually broadcast an aura of good-humoured amusement. "Today's discussion is a matter of some sensitivity. As you know, we will be arriving on Sanghelios within the week and we must…come to an understanding on a vital matter."

Evan took a seat in the chair across from Lak. "Oh?" he inquired, hoping he sounded calm and reassuring, though his mind was racing. They'd had the toilet and sanitation discussion last week, after all...

Lak sighed, and looked Evan in the eyes, as though he had decided that he might as well be blunt. "Are you married?"

Evan blinked. "No," he replied.

"Do you have a bondmate?"

"No," Evan said slowly, not sure what the difference was between "bondmate" and "wife." "I'm single," he added, just to clarify in case "bondmate" was Sangheili-ese for "girlfriend."

It hadn't made sense for Evan to pursue a serious relationship given his job and the realities of the war. He didn't think it would be fair for him to have a wife he only saw every few years, or children constantly at risk of becoming orphans. Evan had kept his relationships strictly temporary, and that had been enough, though he'd hoped that if he survived the war, he might find a nice girl and settle down.

"But you have had mates, yes?"

"I've never been divorced, if that's what you're asking."

Lak tilted his head. "What is divorced?"

"Er..." Here it was, another moment of cultural disconnect. "Divorce is when a marriage ends because the two people aren't getting along with one another."

Lak's expression was probably a scowl—the sheer number of pointed teeth displayed made it clear that the Sangheili did not like the idea. "Such is a rare thing on Sangheilos, and a grave dishonour. Better to send assassins after a dangerous spouse."

Evan was good at hiding his reactions, but damn, what did you say to something like that? That he supposed Sanghelios didn't have much of a domestic violence problem? Or that it wasn't fair if there was no other way out of a poorly matched marriage beyond hiring a hitman?

It was best to reflect the question back at Lak. "I don't think I understand what you mean by mates."

Lak blinked at him with large amber eyes. "You have had sex before, have you not?" The Sangheili seemed embarrassed.

Oh. Evan was a bit embarrassed himself as he nodded in the affirmative.

"And do you have a consort, or several?"

Now Evan was starting to figure out what Lak wanted to talk to him about. He wasn't sure whether to be impressed at the thoroughness of the Sangheili's attention to his welfare, or to tell the alien that he had already taken care of this himself, thank you.

Except that if "bondmate" was "girlfriend," what did "consort" mean?

"I need some clarification," Evan said slowly. "I understand "wife," but I don't know the difference between "mate," "consort" and "bondmate.""

Lak nodded. "A mate is someone you have had sex with."

Well, that was blunt.

"A consort is someone with whom you mate regularly. This can be a simple matter of mutual entertainment, or a compatibility test prior to bonding. The relationship is signified by the wearing of a bracelet and, while it may not be an exclusive relationship, most individuals, upon seeing the bracelet, assume the wearer is unavailable. This relationship has no legal authority and is a casual social arrangement."

Girlfriend, Evan translated.

"A bondmate is someone to whom you have committed your life because you love the person. It is a holy union sworn before the gods."

Evan scratched his head. "How is bondmate different from wife, then?"

Lak blinked. "Marriage is a legal and political arrangement, entered to cement alliances, usually through mingling of genetics. Its purpose is to produce multiple young from the same parents."

Evan felt his lips pucker. That was blunt as well. And Lak wasn't done.

"This is why marriage is restricted to one male and one female, while the other relationships may involve individuals of any gender or even multiple individuals. Swordsmen and Priestesses, to spread their superior genes, are forbidden to marry; many councillors and kaidons remain single in order to do the same, though often politics demands marriage in time. No one of the opposite gender may mate with a married Sangheili save a Swordsman or a Priestess. Sangheili with opposite-gender bondmates forfeit their ability to have sex with them upon their marriage to another." Lak closed his eyes. "The most fortunate among us have the same person for both spouse and bondmate."

Every time Evan thought he was comfortable around Sangheili, they'd do something like this and remind him of just how alien they were. They had different words for "marriage for love" and "marriage for business," but they didn't have a word to distinguish between "girlfriend" and "booty call."

"Well, to answer your question, Lak, I don't have any of those. I've spent my lifetime at war, in dangerous occupations, and I didn't think it was worthwhile to tie myself down to a wife and kids—or a steady girlfriend..."

Lak raised an eye ridge.

"A consort," Evan clarified.

Lak nodded.

"To have someone like that when I was always away fighting."

"You are a proud warrior," Lak said. "This is good." His mandibles fluttered. "Do you prefer females?"

Dammit, but that was a nosy question, out of nowhere! "Yes."

Lak nodded, seeming pleased. "That is good as well."

Evan wondered if the species was homophobic. His best friend was gay, and Evan didn't like the way some people on Earth treated him, as though Carl's loving long-term relationship suddenly made him morally questionable simply because he was married to a George instead of a Georgina. On the other hand, Lak had just spoken of same-sex and even polygamous relationships in the same casual tone as he'd used to discuss marriage, so perhaps not.

Evan took a deep breath. "This is potentially embarrassing, isn't it?"

Lak nodded.

"Well, I can save you the trouble. You know we have support staff aboard, coming to staff the new Earth embassy in Iruiru, and several of them are female. I found one of them particulary appealing during our pre-mission briefing week, and if I'm mistaken and she doesn't find me interesting as well, I have several other options. I'm pretty sure I'm covered in this department, Lak."

Lak laced his fingers together again. "I am not merely inquiring about your opportunities for sexual companionship."

Evan felt a sudden strange knotting in the bottom of his stomach. His instincts had saved his life several times during the war, and right now his instincts had been jolted rudely awake by the fact that Lak had more in mind than ensuring Evan's needs were met.

"Lak..."

The elder Sangheili shifted sideways in his chair. "The majority of the Sangheili councillors have voted for a formal alliance between our peoples."

Evan was confused. "Yes, that is why we are establishing an embassy on Sanghelios, just as you have one on Earth."

Lak scratched at his lower mandibles. "This embassy concept is new to us as a species. Yes, the Covenant taught us to maintain a presence in the company of other species, but...it is not how the Sangheili people have traditionally behaved. On your world, the paresence of Usze 'Taham and N'tho 'Sraom in formal garb is sufficient to indicate to your people that we have become your allies. On our world, the people will demand something different." He let out his breath slowly. "According to Sangheili tradition, the Councillors have decreed that you be married."

Lak's revelation hit Evan like a sucker punch.

The reason behind Lak's questions became suddenly and horribly clear. It was too late for Evan to lie and say he had a wife back on Earth now. He'd just told the Sangheili that he was single and unattached—suitable marriage material—except...

"But you place such importance on bloodlines," Evan argued. "Surely the Councillors understand that a Human and a Sangheili are too biologically different to reproduce."

Lak nodded. "This was a major factor in the debate. However, in the end, the formality of the union was judged more important than any theoretical young. For centuries, Sangheili have celebrated the cessation of hostilites between keeps, clans or city-states with marriages. There is no better way to illustrate to the average Sangheili citizen that Humanity are our allies."

Evan felt sick. He was all too aware that the common citizen could be completely unaware of events outside their experience, whether that be trying to explain the horrors of combat to someone who'd never experienced them, or the higher workings of government to the man on the street.

"Is there any way out of this?"

Lak regarded him sorrowfully. "I regret that it would be taken as a grave insult, or at the very least, a reason for suspicion."

And he couldn't afford that. Humanity needed its alliance with the Sangheili in order to rebuild.

"I have done my best for you. I will seek for you a mate with qualities that I believe will compliment yours."

Evan was not a diplomat by training. He could not soften the question that leapt from his mouth. "Are you telling me I have to have sex with an alien?"

Lak's mandibles shivered. "It would only be mandatory once."

Evan wasn't sure if that was good or not. Apparently he was not in for a life sentence.
But still….

He looked at Lak. The jaws, the scales, the strange legs, the sheer size…he'd managed to consider them as people and not animals, but to fuck one?

It was a mission, Evan thought. He had to think of this situation as a mission. He could do anything once.

God, what did the females even look like? Evan had never seen one. He wondered if it would look at all female. He wondered if they might possibly be even more weird and alien than the males.

"We are not unreasonable, Evan," Lak said. "I argued to the Council that you would naturally prefer the sexual companionship of your own kind. I told them that you would no more welcome a Sangheili mate than they would enjoy breeding with a Human." The Sangheili tilted his head. "The Council are not impractical. They know that you will likely seek Human mates outside your marriage, and they are willing to give you the same leeway they would give to a kaidon or war hero, many of whom have historically been less than faithful to their wives. If you are discreet, they will look the other way. I have insisted that this be made clear."

Evan felt a small measure of relief that this marriage did not mean the end of his sex life with human women.

Lak continued, "So, you would need only mate with your new wife once, to consummate and seal the marriage."

Evan let out his breath. "So after that, we could go on our separate ways?"

Lak fidgeted. "You would, of course, be expected to live in her company, and she would go with you to public events."

Evan nodded, trying to assimilate this information into his mind, when all it seemed to want to do was spin incoherently. "But after the, er, first night, we could find other partners?"

Lak's expression suddenly saddened. "You could."

Evan pulled in his breath. "She couldn't?"

"Concession would be made for you as you are not a Sangheili. She is, and she does not have the rank and power of a Priestess to exempt her from the rules."

So, whoever he married, he'd be able to fool around with impunity while she was condemned to a life of celibacy, unless he was willing and able to give her some pity sex now and then. The idea was horrible either way; he didn't want to fuck an alien, but he also didn't want to leave the poor girl sexually frustrated for the rest of her life. He could only hope she didn't want him any more than he wanted her.

Then Evan's brain filled him in on another detail.

Lak had spoken as though someone had already been chosen.

"Hey," Evan said. "Do I at least get to pick my own wife?"

Lak's eyes dropped. "The Council went to considerable effort to ensure that certain...criteria...were met."

Married. He'd just get off the ship and he'd end up married.

"Do I even get a chance to meet her before the ceremony?" he asked desperately. "An opportunity to ask for a second choice if it turns out we can't tolerate one another?" He swallowed, his mouth dry. "I do not want to insult you or imply that I question your judgment. I merely mean to state that as you have not actually lived with this female, you can never really know what someone's like until you live with them and…"

He was babbling. He cleared his throat and started again. "Lak. Let me be frank. I'm beginning to understand how important this alliance is, not just to the Council, but to Humanity in general and myself in particular. I know you have my best interests in mind and you're doing this as a way to help myself and my staff be accepted in your people's culture."

Lak nodded, looking relieved.

"So I know that if I say no to the girl in question, the Council will choose me another. And I'm aware that I can't say no indefinitely..."

"Business will not begin until you are married into our culture," Lak said softly, confirming Evan's analysis.

"But...from a culture where people are free to decide who they will marry, if at all...I want at least the chance to meet my future wife and, if it turns out we're obviously incompatible, the opportunity to pick from a list of candidates."

The Sangheili held his tongue. Evan took that as a good sign.

"I know you read my files and I'm sure you did your best, Lak, but the fact remains, you haven't known me very long and you don't know much about me as a person. Whoever I marry is going to have to be around me a lot, at a lot of official functions....and I'm a human being. Our culture sees husband and wife as a pair, not just two people who meet up sometimes for sex."

Lak thought for a moment. "If our choice of female does not please you, we will present you the short list of candidates for you to choose a wife. Is this acceptable?"

It wasn't, not really, but Evan knew it was as good as he was going to get.

He nodded, feeling as though he'd just walked into a jail cell of his own volition. "When will I meet her?"

Lak let out his breath. "You have already met her."