Ashe
Stan is coming, obviously. As if he'd miss a quarry party. He'll drink a lot of water and bring healthy snacks for people, like granola bars or trail mix and stuff. He's also going to be keeping an eye on any alcohol related shenanigans so that Eddie doesn't have to worry about that. Lots of water and good choices. He will definitely just jump straight into the quarry because he's done it a million times and it is no longer concerning. He'll be pretty social, but probably not get involved in the water fights. Probably take some time to bird watch from the shore or look for turtles with Bill.
Squall is coming because Bev declared it so and he pretty much does what she says because she's one of three people he knows how to interact with. He's not going to be fazed by jumping off high places. He's done way scarier things. He'll be super awkward probably, because he's not very adept at social situations, but he'll try to get along with people. He's going to drag Seifer along if he can. Might partake in the drinking later if it seems like most other people are.