The couple that they meet (Jack and Eve) are from Summer Scent. Jaye has a pretty long cameo in that game as well, and there's other fun interplay, like CS's naughty French Captain as a reference to SS's dev, The Naughty Captain, who is French.
The signature style of that game is that it's quite drama heavy, and there are a LOT of branching routes that interplay for how the game can go (not just which girl do you romance, but is your character supportive, controlling, or batshit nuts, etc.). That makes the choices you make along the way extremely important for how things proceed, and sometimes this is a good thing, but sometimes (rarely, one big exception I allude to here) it means things like hanging out with the wrong person at the shopping mall can get you a bad ending later on in a certain route even though it wasn't very obvious at the time which choice would lead to a certain conversation. To mitigate that, the game has a built-in walkthrough (lighthouse mode) where you can set what route you want to follow and it will give you nudges if a choice can push away from that route.
If those don't sound like your kind of game, don't play, but if they do, it's quite solid. Play through the existing content once blind and see where you end up, then try playing with lighthouse on to pick your route if it went off the rails or you got a bad ending.
