Kio
As a morning person, Kio is up BRIGHT AND EARLY AND ENTHUSIASTICALLY, so he probably gets into a lot of early-morning arguments with people who just want him to shut up and calm the fuck down. Kio can usually be found eating and snacking his way around camp, or just chilling around in Cabin 10 with the pie vine and Oscar. He also finds it his personal duty to babysit the Zero boys, so he also does that quite a bit. He will occassionally paint, but as that requires a lot of materials not always readily at hand, he doesn't do it that often. Sketching is another hobby. Gardening is one, too! Kio's also the sort of person who listens to music and sings along really loudly without realizing it while working, so if he's painting or trying to garden, chances are he's doing that.
Youji
Let it always be assumed that Youji and Natsuo are together whenever we're not playing them. Chasing animals, kicking things, defacing property, leering at pretty girls, stealing food, bathing; all of it together. Youji's also a big fan of the internet, and will spend hours and hours on his laptop looking up things like torture methods, urban dictionary, chick tracts and, yes, probably Fandom_Wank. Not that Youji and Natsuo sort of have the cabin to themselves, they probably spend their days tearing it up and doing crazy stuff in it. There are possibly tiny animal corpses under their bed. WHO KNOWS?
Kimimaro
Kimimaro just trains like crazy. Out in the woods were no one can find him and observe and strategize against his style (yes, he's paranoid like that). If he hears someone coming? Will pick up and get the heck out of there. He usually can be found around the barrier, too. Not touching it, but possibly just staring at it and waiting to find... something that will help him get out. Also, despite living with Rue, I always sort of assumed they don't see each other that often, since I play Kimimaro as getting up pretty early and getting out of the cabin for the entire day, and sometimes not going back for days at a time. He's not the sort to laze around all day at all.