"Are you sure you have enough energy for this? Will it even work?" you ask as Bucky sets you down on the mattress. You look up at him with worry lining your features, you may have gone through hell and back, but he hasn't fed since you've been gone, either.

He crawls forward and sits on his knees, pulling your body into his lap. "Only one way to find out."

"Bucky, what if I hurt you?" You place your hands on his shoulders to stop him when he tries to pull your hips closer.

"You won't," he assures you.

"But what if I draw too much energy?"

"You won't," he repeats a little more firmly.

"But-"

"Lumina," he cuts you off, hands squeezing encouragingly at your hips. "You can do this. Your instincts will guide you. And I'll be with you every step of the way."

You tug your bottom lip between your teeth. "But what if you pass out," you ask timidly.

He chuckles, grinning crookedly. "Then I'll congratulate you when I wake up."

You give him an unamused look. "That's not funny."

Your words only prove to make his smile widen. He leans forward and places a quick peck on your nose. "You'll be fine, Lumina. I promise. This will complete your transition. Besides, you need the transference to heal the last of your injuries. Your blood has given me enough energy to do this for you. It'll work."

You release a shaky breath, you can feel yourself conceding to him despite your reservations. "Alright."

You run your fingers across his shoulder and down his chest. You work your way down the planes of bare skin until your hand wraps around his already half hardened cock. Bucky comes to life at your touch, a deep groan rumbling out of his chest. "God I missed you," he breathes, leaning his head down and burying his face against your neck.

You run your free hand through his hair, cradling the back of his head against you. "Missed you too, Buck."

He uses his nose to tilt your chin up slightly, giving him access to run his lips across your neck. You continue to give him lengthened strokes, feeling the prickling of awareness develop in your core the longer you have your hands on him. It's almost like you're teasing yourself; having him so close to where you want him most, but denying yourself that pleasure. You feel that throb of heat between your legs; the flush of wetness as your body begs to be filled.

The veins in Bucky's cock pulse beneath your fingertips, his body just as desperate as yours. You trail your hand down his length and passed his base, gentling cupping his balls against your palm. His hips involuntarily jerk forward and you feel his shaky breath against you neck.

"You trying to end things before they've even started, Lumina?" he releases a low groan when you squeeze him teasingly.

You nip playfully at the shell of his ear. "Just wanna feel you."

You can feel the muscles in his thighs tense beneath you has he tries to fight his body's reactions to your touch. He's so sensitive to you that it's almost too much. His fingers dig into your hips, pulling you closer. "Lumina, please," he huffs before giving you a responding nip against the hollow of your throat.

You bite your bottom lip, releasing a small whimper. Having mercy on the both of you, you lift up slightly onto your knees. Rocking your hips forward, you align him with your entrance, his head gliding easily against your slick folds. You feel a rush of new wetness between your thighs as your body thrums in anticipation of his closeness. It sends a shiver running up your spine. You were used to your body opening up to his during your initial coupling, but this was an entirely new sensation. He'd barely even touched you and your body was already keening for his.

When normally you would have prepared him a little by coating him in your slick, you find yourself just sinking down on him and going without. That seems to have been the right thing to do, when just his very tip seems to send a bolt of lightning through your whole system.

Bucky must have felt it too, you realize when he jumps slightly from the shock before he jerks forward and fills you with one solid thrust.

"Oh Go- Ah!" your words transition to a loud moan, the most intense pleasure you've ever felt in your life sending you into a frenzy. Heat rushes through every vein and nerve ending in your whole body. It's like sinking into a hot bath after a day in the snow. Your body feels encompassed in warmth and security. And the feeling only heightens when you feel Bucky's hands against your back, pulling your body closer to his. The two of you shudder, completely wrapped around each other.

You release a stuttering breath. "Is this what it's like for you every time?" you question breathlessly, wondering if this is an Incubus reaction.

His face remains firmly planted against your neck as he shakes his head. "No. This is the merge," he explains, his voice tense with restraint. "One soul, one body. Our souls will forever be locked together, so now when our bodies become one, it'll feel like this." You can feel his thighs trembling slightly. "Fuck, you feel so good, Lumina," he huffs, his breath fanning across your neck.

"Bucky..." you whine quietly, basking in the feeling of being connected to him so intimately.

"Just give me a sec, sweetheart," he groans when you shift your hips ever so slightly.

You do your best to keep still, but your muscles seem to ache the longer you don't move, especially between your thighs. You gently tug at his hair to get him to lift his head. Your eyes wash over his face, noticing the tension in his brow as he tries to gain control over his body. You cradle his jaw in your hands and pepper kisses across his face until the tension begins to ease away.

"I love you, Y/N," he whispers to you as your lips brush against his jaw.

You pull back, looking at him with all the tenderness and warmth in the world. "I love you too, Buck." Leaning back in, you capture his mouth. You muffle each other's moans as the bond between you two only seems to heighten further. You can feel your energies mixing, the two of you becoming one in every sense of the word.

Bucky's hands glide down your back until he's cupping the globes of your ass. He encouragingly rocks your hips forward, giving you the okay to start moving. You roll your hips experimentally, feeling the way he shifts inside you. Even the smallest movement seems to make the pleasure more intense. It's like a ripple effect, starting at your core and moving outward until your hair is standing on end.

His tongue dips into your mouth, the taste of him making you see colors. He's always had a unique taste, but now it was like you were experiencing him on a whole new level. Flavors you didn't even know existed burst against your tongue. Scents so pure and satisfying fill your lungs. The touch of your fingers against his skin is so smooth, and the awareness of his hands on you makes you tingle. The sounds of your mixed moans and labored breaths a symphony to your ears. Everything that was Bucky could make your head spin before, but now it felt like you were flying.

This was more than sex and even more than love making. This was the result of merging two souls to form one. A bond so unbreakable, it could surpass the impossible. You'd give absolutely anything to this man. And now you've given him the only thing of value that you possessed. Yourself. And he was more than willing to do the same for you.

"Oh Bucky!" you sigh, your head tilting back in a moan as he begins to drive up into you.

"Lumina, you need to start concentrating on the transference. I can feel your body trying to give up its energy instead of you taking mine." A crease develops in his brow as he tries to keep his focus, so he can guide you properly.

Your own brow furrows, your hands clenching his shoulders. "What do I do?"

"Can you feel my energy?" he pants, hooking an arm around your waist and pushing your chest flush to his. The more skin on skin contact the easier the transference will be for you.

"Yes," you respond.

"Concentrate on pulling it in. Feel it consuming you."

You release a soft gasp as you do what he says and you begin to take in his energy to feed yours. A sort of heat settles deep in your belly, like when you drink your favorite hot beverage on a cold day. It's like feeling the afterglow of sex while you're still in the middle of it. Like pure satisfaction seeping into your blood.

"That's my girl," Bucky praises when he feels it working. "Shit, you're a natural," his jaw goes slack, eyes falling shut as the pleasure of your newfound succubus energy overwhelms him.

"Don't pass out on me, Bucky," you warn mildly.

He chuckles breathlessly. "I won't. But I don't think I'm gonna last much longer either." He takes over a majority of the thrusting, leaving you to bounce on his lap and just relish in how deep he hits you. "Most of the transference will occur during climax," he explains. "The moment you hit your capacity for energy needs to match with your peak. Ready?"

You sink your teeth into your bottom lip before nodding hesitantly. You didn't really trust your voice and you were still scared you were going to mess this up.

Bucky lifts your body and raises up onto his knees before gently lowering you onto your back with your head against the pillows. "You can do this, Lumina. I trust you," he tells you sincerely.

Now that he has the leverage, Bucky strengthens his thrusts, guiding the both of you to new heights. His energy begins to pour into you at a steady rate and it makes your muscles feel like they're turning to jelly. "Oh, James. Oh!"

"Stay with me, Lumina." He drives his thrusts harder and deeper, filling your body with each snap of his hips. "Fuck. 'M not gonna..." he doesn't even get to finish before his entire world explodes. His groan of pleasure vibrates throughout the whole room as he spills into you.

You feel his white hot energy surging forth, filling you to the brim. The suddenness of it is what drives your own climax. You weren't expecting it to be so potent, so thick. You could actually feel the very essence of him merging into you, like when the river meets the sea. It quenches a thirst you didn't even know you had.

The two of your revel in the gratifying fulfillment of hitting your release together. The transference, the soul merge, and the blood bond work in harmony to create pleasure so intense; it propels you both into the stars. You never imagined sex with Bucky being better than it already had been, but this was completely indescribable. The was destiny. Pure fate. The stars finally aligning.

This was the rest of your life.

The two of you remain wrapped around each other until you've both come down from your highs. Bucky carefully sinks his hips back before promptly collapsing onto his back next to you. "Damn. That was pretty fucking incredible," he huffs, more out of breath than usual. "M' already getting sleepy, though," he chuckles with droopy eyes.

You turn onto your side to face him, pushing up onto an elbow. "Did I take too much?" you ask in slight worry.

He smiles reassuringly, "Nah. You were perfect. I'm just gonna need a short nap to recover. I've got your blood in me now, so that should help..." He's barely finished speaking before his eyes close and his breaths even out.

"Bucky?" you call, placing your hand on his chest.

But he's definitely out for the night. Your worry fades slowly when you make sure he continues to breathe. You then find an oddly self-satisfied smile beginning to grow on your lips. You actually managed to get Bucky Barnes the Sex God to pass out after your first successful transference. It was kind of empowering.

You push yourself out of bed and pad over to the joined bathroom to clean up. Bringing a wash cloth back with you, you take care of him too. You pull the blankets in place before crawling under them to join him. You curl your body around his, having to tuck his arm around your waist, because he's too passed out to do it himself.

You give yourself one last moment to watch over him as he sleeps. "Thank you for everything you've done for me Bucky. I don't know what I'd do without you." Leaning down, you place a sweet kiss against his lips before you rest your head on his chest and fall asleep to the steady rise and falls of his breaths.