As promised, a bonus chapter outlining where this story would have gone if I had the time to write it. Hopefully it answers any questions left unaddressed by Club Secret.
Naruto tells Gaara that he wants to visit Jiraiya and receive his training. Gaara thinks it's a bad idea, that Jiraiya will brainwash Naruto into hating vampires. He tells Naruto not to go and they fight. Then Gaara receives a letter from his sire summoning him home. Gaara tells Naruto he has to go and the teenager should stay with his friends while he's away. Naruto asks where he's going but Gaara says it's a secret and leaves abruptly. Naruto goes to stay with Haku who tells him not to rush into anything and that all vampires have secrets they find difficult sharing, especially when they're as old as Gaara.
Meanwhile, Kakashi finds Obito. Obito runs because he thinks Kakashi is after him, but Kakashi catches up to him and shows he's also a vampire. They talk, and Kakashi asks why Obito never tried to find him. Obito says he did but when he found out Kakashi was training to be a Hunter he kept his distance. He was ashamed that he'd gotten Rin killed and thought he'd only hurt Kakashi if he showed up as a vampire.
Gaara arrives at Castle Clandestine to meet his sire Shukaku. Apparently some of the vampires he killed weren't very subtle and word reached Shukaku that Minato had a son. Since nobody's been seen bragging about killing Naruto, Shukaku assumes that Gaara killed them. Gaara worries that his sire will punish him for this but Shukaku doesn't care. He still assumes Gaara is cold and bloodthirsty and is playing Naruto so that it'll be all the more painful when he kills him later. Gaara goes along with the story and asks if this is the reason he was summoned. Shukaku replies it was in part – the Nine Vampire Lords (of which he is one) are in need of a Hunter and he was hoping Gaara might know one connected to Naruto. Gaara gives him Kakashi's name and vague location. Shukaku sends out bounty hunters Hidan and Kakuzu to collect Kakashi.
Kakashi and Obito are trying to reconnect but it's awkward. They get attacked by the bounty hunters and are able to take them out. Kakashi gets worried and convinces Obito that they need to go check on Naruto.
Meanwhile, after spending days reverting to old habits of killing humans to avoid suspicion, Gaara convinces Shukaku that he needs to get back to Naruto so that he can protect his kill. Shukaku agrees and Gaara gets back just before Kakashi. Naruto wants to know what's going on and Kakashi gets suspicious when he hears Gaara's been gone for a week. Obito confused, but he's sure he recognises Gaara from somewhere.
A week later Shukaku hears his bounty hunters failed and calls Gaara back, telling him to bring Naruto. Gaara say going to take Naruto to meet Jiraiya, but Kakashi suspicious and say he's going to do it. Gaara say fine. Naruto happy, but less so when Gaara say he has to disappear on business and Kakashi and Obito will have to do it.
Naruto and the two vampires find Jiraiya who isn't interested in training him. He thought Kakashi would get himself killed or turned into a vampire and he's glad he was proved right. Glad his head is in a better place though. Naruto attempts to convince Jiraiya to change his mind. He starts talking about Gaara and Jiraiya recognises him, his sire, and his rep. Obito realises where he remembers him from. Kakashi say Gaara was likely the one who sent bounty hunters after him. Naruto objects, but it gets Jiraiya thinking. He says maybe Gaara has changed whilst away from his sire – who's powerful and malicious. A sire can always find their progeny and maybe Gaara let Naruto go in order to keep him safe. Or maybe it's a trap and Gaara is going to lead the vampires right to them. Either way, something is happening. Jiraiya had recently been approached by the Hunter Council asking him to help them. He'd refused because he's retired and doesn't want to get involved. But he's worried and he'd liked Minato, so he agrees to train Naruto.
Meanwhile, Gaara has to explain that the Hunter wouldn't let Naruto leave and he didn't want to blow his cover unless explicitly ordered. Plus, he thought Shukaku wanted the Hunter alive and it would have been quite suspicious if he was seen transporting two prisoners. Shukaku gives him the benefit of the doubt, but still punishes him with a little psychic torture.
Naruto begins his training. Mostly it's building up his fitness and some weapons training. Kakashi and Obito occasionally help but a lot of the time they spend together talking about their lives and remembering the past and getting closer.
Jiraiya explains that although Hunters are usually solitary, there is a governing body that is supposed to be there to aid them in times of crisis and make sure information is passed on to all. When hunting runs in the family you're connected to the Hunter Council. If you're an outsider like Kakashi was then you learn about the Council when you're ready.
Next day another one of the Nine Vampire Lords, Kyuubi, arrives. He wants to have a conversation with Gaara. Tells him that in certain parts Hunters are attacking more and more vampires. The vampires have had enough and want to wipe them out. There's going to be a full-on war soon. But first they need a Hunter with information on the Council of Hunters and their recent movements. Kyuubi isn't as blind as Shukaku when it comes to Gaara and knows that he's not as bloodthirsty as he used to be. He promises to keep Naruto safe if Gaara gets him a Hunter. Gaara agrees for Naruto's sake and because Kakashi is a problem he'd like to get rid of.
A Hunter calls on Jiraiya asking him to join the Council. He says there's talk of war coming, and Jiraiya agrees to go to gather information. Naruto wants to know about his training. Jiraiya says it will take weeks and he won't be ready for a war if there is one. Naruto asks if there is anything he can do. After much pleading Jiraiya admits he could transform him now. A Hunter is given a mixture that is part vampire blood, part other magic. They train first because it's easier to reach your physical peak as a human and then become a Hunter than to become a Hunter and then do all the training. But since Naruto needs all the help he can get Jiraiya will make an exception. He gives Naruto the potion but nothing happens. Jiraiya says he thought it might happen. When he met Naruto's mother years ago he guessed she might have the fabled 'Gift of the Whirlpool'. The Gift is an ancient bloodpool trait that gives all those who know how to use it the power to render a vampire powerless. Only one family ever had the Gift and it was rumoured they'd all been killed by vampires before they could learn how to use it. Naruto also has the Gift, which means he can neither become a vampire or a Hunter. Disappointed, Naruto, Kakashi and Obito head home.
Gaara is waiting for them, and Kakashi immediately confronts him. Gaara admits that he has made a deal which is basically Kakashi for Naruto. Naruto is furious but Gaara says he didn't have much choice. They'll find out Kakashi has no information and recruit him to their side when they see he's a vampire. Gaara couldn't refuse a Vampire Lord unless he wanted them all to be killed or captured. He says if they go peacefully then Kyuubi will pretend at civility because that's what he does. If Kakashi cooperates then they'll treat him well because he's a vampire. They can try to run but if Kyuubi really does have spies watching them then they'll need to run fast and hide well. In the end they decide to go to Castle Clandestine.
At the castle Kakashi is taken for interrogation, but they don't torture him because he's a vampire. Kyuubi works out he doesn't know anything and says he's free to go. The Vampire Lord then turns his attention to Naruto. Naruto is terrified of all the crazy vampires that kill the humans they feed on. He mostly hides in his room or with Obito. He starts to become scared of Gaara, who is much colder here. He says he wants to leave but the vampires make it obvious he's not going anywhere.
There's a meeting at the castle of the Nine Vampire Lords. Some of them want the war, others don't. These are the vampires who think humans are more than just food. They help Naruto, Obito and Kakashi to escape. Gaara has to stay behind because Shukaku will be able to find him. Naruto objects but Gaara convinces him that this is how it has to be for now.
Shukaku tortures Gaara and tries to get him to give up Naruto's location. Gaara doesn't know so can't tell. Shukaku reveals that the reason Gaara can't remember his human life is because he forced himself to forget his sire massacring his family and then keeping him as a blood slave until he was 19. Gaara decides then that his loyalty is only to Naruto, but he has to be careful because Shukaku still has power over him.
Naruto heads back to see Jiraiya. Jiraiya says they can stay with him but they should be careful. The war with vampires is all but declared and they're going to want to recruit Naruto. Naruto say not want to go to war; want to learn how to use his Gift. Jiraiya give him directions to the Cave of Discovery. If he goes there he might learn how to use it.
Naruto travels to cave and undergoes a series of hallucinogenic visions that end with his ancestors teaching him how to take a vampire's powers. He tells Kakashi he wants to use his Gift to rescue Gaara. Kakashi advices they gather more people before attempting to infiltrate the castle. They go to meet the Hunter Council: the 5 Kages (with Baki in place of Gaara). Naruto tells them that not all vampires are bad and Kakashi and Obito are good examples. Half the council agree, the other half think all vampires need to be wiped out. They discuss the matter and decide that either way taking out Castle Clandestine is a good thing and offer Naruto as many Hunters as needed to save Gaara. Kakashi organises the team while Naruto calls Zabuza and asks if there's anything he needs to know before he tries to do this. Zabuza offers advice and asks if he needs help on the potential suicide mission. Naruto says it would be safer for him to stay away; he doesn't want him killed by friendly fire.
Plan made, Naruto and gang infiltrate the castle as quietly as possible. In the end the alarm is raised and an all-out battle occurs. Naruto rushes to the dungeons and rescues Gaara. During their escape Shukaku appears and Naruto takes his power. Gaara gets his revenge by killing him. Naruto also has to take the power of the other Vampire Lords who try and fight. Those uninterested in a war and killing humans escape. Kyuubi also escapes.
Naruto returns to the Hunter Council, who want him to take out the other Vampire Lords. He says there's only one he would help them take down and he's not really interested at the moment. Maybe in a few years but he's a little traumatised right now. Council discuss and decide that's fair enough. The remaining Vampire Lords (minus Kyuubi) want a treaty signing anyway. They'll police vampires better and there won't be any killing if the Hunter's promise the same. The Council promises to attempt the treaty, so long as they can monitor vampires and kill any they see breaking the treaty. The treaty is approved and Naruto heads home knowing there are going to be lots of problems, but hopefully they'll find a way to make it work.
Naruto chooses to stay with Haku for a bit to try and forget all the murdering. Then he goes to live with Kakashi, who has bought a house with Obito. Now that the two are together he's more chilled about the whole Gaara situation, but he does still act like a protective parent who disapproves of the boyfriend. Gaara is actually glad for the space after the time in Shukaku's dungeon. He's starting to return to being the vampire he was before all this happened, but he still doesn't entirely trust himself. He's taking it a day at a time, but he still loves Naruto and Naruto still loves him. They have problems but they're working through them.
Kyuubi is out there plotting, but for the moment all is peaceful and positive. Like everyone he's waiting to see if humans, vampires, and Hunters can all live together, and waiting for the fallout if they can't.