Oh, well I think we could definitely keep them separate for the majority of the first day, but I was thinking further ahead. Like, for comedic effect they keep ending up in situations together to the point where they have no choice but to become friends. Like being grouped in the group project together as a complete coincidence, etcetera. 
Also the whole plushy thing wasn't really inaccurate. I've got a whole closet full of them. They keep spilling out onto my floor. Yamamoto definitely likes them, but he probably wouldn't want people to know that. Me, I don't mind, but he's got friends and a façade to keep up. He's cool on the outside, but secretly a huge nerd who loves cute things.