A/N: Warning: Dub-Con in this chapter! Read at your own risk!
Khan decided to wait for Jim in his quarters. He easily bypassed the code with an override sequence and made himself comfortable in his usual chair, mindlessly fiddling with a rook. He took the time to reflect on everything that had occurred since his arrival on the S.S Enterprise. Originally he planned to seduce the Captain in order to use Jim's feelings for him to manipulate his leadership in his favor. Jim was starving to please. To Khan this was as obvious as that mole behind Jim's left ear. He could only assume this characteristic reflected some childhood deficiency in affection. Most likely abuse or neglect from his parents or siblings. Khan had recently gathered all Kirk related history from the Star Fleet database, by hacking into the highly secure archives from Spock's computer. He smirked thinking how the half-vulcan menace would react when Star Fleet accused him and called him in for questioning.
Still he could remember well a time when was all to eager to corrupt the naïve captain. He assumed it would be easy to worm his way into Jim's heart. However he now realized how foolish it was of him to underestimate the power of human feeling. Jim's attachment to his former Captain was far beyond anything Khan could have fathom. He in all honesty thought that after Kirk pummeled him ineffectively on Kronos, all personal resentment between them was moot. He never expected the depth of that betrayal. Jim couldn't stand him, yet strangely couldn't help but subconsciously return Khan's flirtations. Then came the unexpected rejection, that struck harder than Khan had anticipated; perhaps because it was so unexpected. When he arrived at Jim's quarters that night he was absolutely confident that Jim asked him over to engage in sexual activity, to which all the flirtation has inadvertently been leading to. When Jim proclaimed him unattractive it struck harder than expected and left Khan feeling strangely empty and cold.
He acted irrationally storming out in a fit of rage, like some common human. Yet he was not in control of these actions. It was like his body acted of its on accord and before he knew it he was back in his quarters beating on his boxing bag with unprecedented ferociousness. Than came the numb phase where every day felt like he was dragging his feet through molasses. It was around day three of this unchanging mood that Khan came upon the sudden realization that his corruption of the captain had backfired in the most horrible way. It had turned on him and deftly used his own ignorance against him to manifest feelings he never experienced before. Khan felt genuine desire to court the blonde because he was Jim Kirk the man and not Jim Kirk the captain. Even thinking of Kirk as a weapon or a tool somehow felt hollow and meaningless now. Instead he found himself dreaming of holding Kirk, descending that tanned body in a trail of kisses and tasting parts of him hidden from view. He wanted to own Kirk.
It occurred to him shortly after they were bought to medical bay, to tell Kirk the truth about everything. He felt guilty enough lying about not remembering their past. But it pained him more that Jim had no idea how little the Vulcan therapy had really affected his psyche. Even though these feelings of dominance over other species were less pronounced he still felt a twinge of desire to be in complete control of everyone he encountered. It wasn't until the Gurachii that he realized that your past had a way of catching up to you when you least expected it. The trial was painful to observed, especially when he was repeatedly accused of terrible acts that began to flood his memory and fill the blanks at the mention of dates and places. People he slain, places he demolished. All in the name of power that meant so little to him now.
Khan knew there was a very real chance of loosing Kirk for good if he came clean about everything he remembered. Most likely the blonde captain would deposit him and his crew on the next desolate planet and fly away. He wasn't even sure it would go that far. Perhaps Kirk will simply have him cryogenically frozen and left in the metal tomb to rot for all eternity. Still the thought of Jim finding out from someone else, like that Vulcan FO, made Khan feel sick to the stomach. He decided in that moment to tell Jim everything the moment he stepped through the sliding front door. He could not build this relationship on a foundation of lies, it would only destroy it.
Jim stormed into his quarters, pissed beyond measure. He would have a quick shower then storm over to that traitor's quarters for a serious beat down. Enough is enough. As much as he wanted to doubt Spock, he knew his reasoning was solid. It was very probable that Khan became aware of his involvement in the Gurachii massacre during the course of the trial. Yet still he failed to inform him of this, choosing instead to act the part of the unfortunate victim. He was right all along, this monster was never going to change and nothing in the universe and universes beyond it could ever change him.
"Kirk, you're back." Jim stiffened at the familiar voice and spun around to glare at Khan. He looked so comfortable reclining easily in his usual seat, a rook spinning in lazy circles between his fingers. The sight of his nonchalance pushed Jim over the edge. He took three steps across the room and swung his fist hard into the brunette's perfect cheekbone, satisfied at the loud thump that accompanied the pain in his wrist. Khan turned his head to face Jim with a startled wide-eyed gaze.
"What is the meaning of this Captain?"
"You lying sack of shit," Jim swore and tried to swing again but his wrist was captured mid air. Khan lowered the hand to rest on the chessboard.
"What…" he began, starting to feel slightly numb with fear as realization quickly dawned on him. There was only one thing that would anger the captain to this extent.
"You know what this is about, don't play cute you despicable freak." Hissed the blonde challengingly and glared at the other with narrow eyes that appeared to have darkened in anger. "I know about Gurach Khan, I know about what happened to them years ago, or more precisely who happened to them. I wondered quietly to myself why your name came up so often during trial while mine hardly came up once. It didn't occur to because as I recently found out I am an idiot. An idiot for letting Spock do that Vulcan voodoo on you, an idiot for letting you come with me on this mission and most importantly an idiot for trusting you." The last part was yelled with enough force to drizzle spittle on Khan. The brunette for once lost his stoic composure and looked equal part remorseful and terrified. Jim assumed he was afraid of being frozen again or simply destroyed to save future generations the trouble; but Khan in fact had a completely different reason. Jim's words made his chest burn strangely and very unpleasantly. Like any minute now his pummeling heart would burst through his rib cage and fall on the floor.
"Jim, I made a mistake in not telling you this earlier. You must no reject me because of it."
Jim snorted and briskly stalked to the front door, jerking his hand free from Khan's iron hold on his captured wrist.
"Get out! I never want to see you again. Tomorrow I tell Sulu to dock at the nearest Star Fleet base where you and whichever crewmembers wish to leave with you, will be deposited. You are a monster Khan, I fooled myself into believing there was more to you than selfishness and lies."
Khan's expression was heartbreaking. His wide eyes looked strangely pink and swollen and if Kirk didn't know any better he would have said the brunette was very close to tears. He tore his eyes away before they convinced him to reconsider.
"Get out. Now."
Khan gracelessly dragged himself from his seat and uncharacteristically stooping his shoulder, made his way to the front door. But when he brushed past the captain on his way out he was suddenly overcome with monstrous rage. Rage like he never felt before directed at the unfairness of this dismal scenario. How dare Kirk reject him like this? Who did he think he is? Spinning around he pressed the button that slid the entrance shut and grabbing Jim by the scuff of his shirt, slammed the unsuspecting blonde against the door. He growled like an enraged wolf and pressed himself hard against the smaller man until he felt Kirk struggle to take in oxygen against his crushing hold. Smashing his mouth hard against the gapping lips, Khan stole what little oxygen remained in his lungs with an all consuming kiss. Kirks started to weaken in his struggle, eventually falling limp against him. Khan smirked and pulled back only far enough to restore Kirk's breath with CPR, glaring triumphantly at the blonde when he began coughing and returning to consciousness.
"I don't think this is going to work Kirk, you dumping me on some god forsaken planet. As you can see, you need me to breath." Kahn canted his hips hard into Kirks and felt relief when a quickly filling hardness met his own. "To live," he added and started aggressively thrusting against the other with enough force to make it both hot and painful for the Captain. Jim stared back into Khan's eyes in fearful stupefaction. Long moments were filled with nothing but the scraping of fabric and hard, desperate panting. Jim might have said something, but Khan kept his lips firmly planted against the captains. Feeling himself getting close, Khan suddenly pulled away, leaned in and bit the side of the captain neck with enough force to puncture the skin. A weak stream of blood flooded his mouth. Khan doubted he ever tasted anything sweeter. Kirk tasted like defeat. Like surrender.
"I am your poison Jim Kirk and your antidote. With out me," he licked up a trail of blood running into the color of Jim's shirt, "you are nothing." Jim came with an explosive scream. He let it wring him dry until his voice cracked and his throat hurt. Khan absorbed the blissful sound for a long moment after it faded, leaving nothing but a pleasant ringing in his ears, he let Kirk sag into his arms and cradled his head lovingly into the side of his neck. Long moment passed in which neither man moved, Khan content in simply running his fingers through messy blonde hair. When Kirk began to stir against him, slowly returning to his senses, Khan shoved him away with enough force to make the smaller man bounce back against he wall and slide in a heap to the floor. Pressing the release button Khan left without another word.
Jim couldn't recall exactly how he had mange to get himself off the floor and to the bathroom, but after an indefinite span of time sitting against the wall he managed to gather enough strength to cover the few feet of distance. Luckily Spock was still on duty and the bathroom was free. For over an hour now Jim felt like he was drowning in here, washing his hair mechanically, over and over like a robot. He wondered vaguely why he couldn't stop. Perhaps he just needed something to distract his hands so he wouldn't do something stupid like slit his wrists. Ok now he was just being over dramatic. Sadly even though he knew that he couldn't help feel used and disgusting, but at the same strangely satisfied. He never had an orgasm like that in his life; and considering how often he had sex that was truly an impressive standard to pass. Still why did his body betray him? He didn't want to enjoy Khan's touch. He detested the man, now more than ever. What he did to him was nothing short of rape, and yet he couldn't make himself acknowledge what happened as anything other than what it was; an epic sensory explosion. As he turned on the water to rinse his hair for the eighth time, Jim couldn't help wondering that if Khan could make him come this hard from dry humping in the hallway, what would it feel like if they fucked properly on a bed.