on paper, it almost sounds like they'd have no reason to not get along. she likes quiet people who mind their own damn business. but i'm not above making cassie petty to facilitate drama! it could've been as simple as he was ahead of her in line at the cafeteria one day and snagged the last of the lemon pudding. on that day, she decided he's space trash and she hates him. cue escalated hostilities over time.