Prompt: Dean Thomas
Dean knows Seamus better than anyone else does. They first met when they ended up in the same compartment on the train in their first year and they've been best friends ever since, doing everything together, telling each other every single thing, always having each other's backs. Seamus is Dean's favourite person in the world.
So he pretends.
He acts like he doesn't see Seamus blush when their thighs brush together by accident, like he doesn't notice the drawings of his face scribbled on spare bits of parchment, like he doesn't hear the things his friend whispers in his sleep and like he doesn't know perfectly well how to interpret the looks Seamus shoots him when he thinks he's not paying attention.
He does see them, of course. Dean knows Seamus better than anyone else, knows exactly how he acts when he has something to hide, knows that for the Irish boy, the rules have changed.
Dean loves Seamus, he really does, but not like that. He's changed the rules, too; he's stopped grabbing his best friend's hand to pull him along, he doesn't throw his arm around Seamus' shoulders anymore, he makes sure to mention the girls he likes.
Dean pretends he doesn't notice and waits for Seamus to get the hint and get over it, so things can go back to normal again.
This isn't worth losing his best friend over.