It wasn't a small act of sin like borrowing something and never returning it, it was something more. Something that'd eat away at him more than he had expected. You didn't attend his school, but he had a bad feeling about it beforehand, silently pleading in his letters to come over this specific weekend, being as vulnerable as he'd only be with you.
The murder of his fellow prefects now former drudge wasn't an easy thing, not something you forget about after a few days. It was something major, something he didn't expect to nag at him so much.
Black lipstick marks pushed into your shirts fabric, trying to escape the outer world. He shouldn't feel guilty, he had agreed to it after all. He was part of it. But he did it to keep up his prefects responsibilities, who knows what else Derrick would've done, right?
His hood he usually wore up had fallen down, exposing even more how vulnerable he was around you, his skin being paler as usual. It was eating him alive. The guilt.
"I shouldn't have.. I shouldn't.."