Take him to your old bedroom

"My bedroom, now!" you strain into a whisper, causing your older brother to practically fly up the stairs at your command.

You leer at your brother's behind as he turns the corner and you soon follow behind, trampling up each stair with a spring in your step. You feel more and more excited the closer you get to the top landing, giving way to hints of nausea and arousal. Simply the anticipation for what you know is about to happen is satisfying. You've always felt something in the back of your mind growing up with the bastard that's now becoming clearer, stoking a fantasy you've never known you had.

You're five steps from your old bedroom when you hear the springs on your old bed strain under the weight of your brother. Your heart is thumping wildly as you turn the corner; you're determined for whatever happens next.

What you see is nothing too far out of the ordinary, simply your brother sitting by the foot of your bed, your previous command keeping him from leaving your bedroom. He watches you enter the room with concern on his face.

"Wh-," your brother stumbles on his words, "Why'd you fucking kiss me? Why'd you make it weird?"

You look him up and down from the doorway before returning to his gaze. A lot of things speed through your mind, thinking of ways to logically explain why you kissed him. It doesn't really matter though, facing the fact you fully intend to fuck his brains out. "I just think you're kinda sexy..."

He stares at you deadpan, raising an eyebrow before sputtering a quick high-pitched giggle, "Pff-oh sure," Your brother alternates between standing and sitting on your bed, trying to rationalize your actions with nervous laughter. You step forward, taking a seat on the bed next to your cackling brother. "...Yeah."

"Oh sure, riiight! I should've known, you've always had a questionable sense of humor," he chuckles, sitting up from a a slouch to better address you . "You're fuckin' with me! You had me there for a second, you weird... bastard."

He continues to chuckle as you snake a hand across the bed sheets, placing your palm over the bulge in his khakis. He quickly notices, and ceases his laughter almost instantly. "Heh wait, what...?"