It’s a mistake, the first time it happens.

Seohyun is stressed and tired and all she wants to do is grab her car and leave this club, but she can’t —not when it’s Tiffany’s birthday, not when they haven’t seen each other in almost a year.

So she stays. Pretty, polite, polished. Barely touches the glass of champagne Sooyoung hands her. “You should pick up smoking,” Hyoyeon says jokingly, takes one last drag before she abandons the cigarette in the ashtray. “It will be good for you.”

Seohyun, without missing a beat, declares, “That thing will kill you.”

Which is ironic, Seohyun realizes later, when Yoona approaches her like a fox lured by the smell of her prey, claiming she forgot her chapstick and needed to borrow hers. She knew it was a lie, a cheap excuse to get close to her, but still . She decided to play Yoona’s game, just for one night.

“I’ve been wanting this for so long,” Yoona confesses later, when her face is between Seohyun’s legs, the victorious grin dancing on her lips confirming her words. Seohyun doesn’t tell her anything back—barely has time to, because Yoona dives in and she forgets she needs to wake up at five in the morning, forgets she has to film with the she calls a co-star, forgets she shouldn’t be giving herself to Yoona like this.

Not this easily, at least.

When it’s over, they don’t kiss. Nor do they talk about what that means for their friendship, if it means something to Yoona at all. To be honest, the only confirmation that Seohyun isn’t going insane and didn’t imagine the whole thing are the hickeys spread all over her neck and thighs, the reflection of her bruised skin mocking her in the mirror.

Never again, Seohyun tells herself the morning after, applies makeup over the purple marks, and in a matter of minutes it’s like Yoona never sunk her teeth into her, never drew more blood than she should’ve.

Pretty, polite, polished. She’ll be fine. She always is.

+

Seohyun could label the other times as mistakes, sure, but she’s never been too good at lying to herself.

It would always happen at group gatherings—Yuri’s birthday, the premiere of Sooyoung’s new movie, Taeyeon and Tiffany’s wedding. Yoona never invited Seohyun over to her apartment, or to the movies, or anything like that. It was as if they were complete strangers the second their friends weren’t around.

Sunny, bless her heart, tried to warn Seohyun once, when they were spending the summer at Hyoyeon’s beach house. “Yoona, she’s—she’s not for you. Just—don’t hurt yourself, okay?”

And she should’ve listened. But later that same day she let Yoona rip her clothes apart and her underneath a waterfall while the rest of their friends were asleep. God, why didn’t she listen?

That thing will