I'm sure you're wondering, how does Katsuki mark his territory on you? Hickeys. His favourite thing in the world is marking you up everywhere; your neck, shoulders, legs and even your upper arms are constantly covered in his love bites... when someone asks about them? He just chuckles and says "It's called 'Showing what belongs to me.'"

It's 3AM. You're in his dorm, making out aggressively. When he says...

"You're mine, baby, my boy."

He licked your ear, his hot breath hit your neck.