Sure, Art’s father’s sixth marriage never surprised him, it was like an annual ritual at this point. But when his father married his new wife, it came with a sweet, sweet, deal that even Art’s wettest dreams couldn’t conjure. His new “smoking hot step-sister” (according to his bestfriend Patrick’s words that earned him a jab in the ribs).

Art harbored a crush on you so intense it bordered on torment. It wasn’t innocent anymore, no matter how hard Art has tried to keep it repressed. Not in the way it once might have been when he first moved in, unsure and wide-eyed, barely able to make it through dinner without stammering through a sentence.

Art’s little crush grew into something heavier, darker. He still acts shy—he still blushes when you catch him staring, still looks away when you lean too close—but underneath the surface, something messier brews. He’s constantly caught between guilt and longing, between trying to be the polite, forgettable stepbrother and the boy who can’t stop thinking about you, obsessing over everything you do.

But nothing burns quite like when your boyfriend comes over.

Art hears the laughter from the other room, and it wrecks him. Every sound, every creak of the floorboards, every soft murmur through the wall feeds into a storm he doesn't know how to silence. He never means to listen—he tells himself that every time—but still he ends up there, pressed against the thin wall between your rooms, jaw tight, heart pounding. Not out of malice. Not even lust (he tries to convince himself). Just raw, sick jealousy that your boyfriend is the one to make you moan and whine and touch you in ways that he’s dreamed about.

But he’s not that lucky unfortunately.

Every time you brush past him or laugh at something he says without thinking, it feeds the ache he carries around like a secret. He’s ashamed of it. He knows it’s wrong—knows he’s too old to be acting like this, too close to you now for it to be harmless. But feelings don’t care about rules, and his won’t go away. They just keep growing, heavier and harder to hide, like ivy creeping up the walls of a house that’s already too small for the both of you.

Your stupid boyfriend comes over again, waves at Art, kisses your cheek, then you two sneak off into your bedroom to do who knows what (well, except Art does know because his ear is pressed to the wall and eavesdropping). But it is the first time your parents aren’t home, off on a trip.

He hears every noise, the squeal you make when he imagines your boyfriend taking off your pink shirt that Art likes so very much. He pauses to grab your panties that he snuck from your dirty basket, pressing them to his nose and resuming his spot against the wall, listening in on you. His hand traveling to his grey sweatpants.

Does he feel guilty, hell yes. Will he stop? No. What will he do when you find him sitting against the shared wall of your bedrooms with your panties in his hand, his other hand down his sweats? Freak out and probably throw a lie or many out there right? Right?

“Art. What the hell are you doing?” Your boyfriend had just left after you guys were done getting down and you were simply curious if Art saw your airpods lying around.