Isa befriended Lea. He found Lea, made the effort to establish a friendship, and to root Lea out of his initial shyness. (Only to later be bombarded with a solar-flare of a personality. He didn't think this was what he was signing up for...) He remains friends with him because he knows what the red head is like when he's distant. Isa's wildly fascinated with the occult. He tells Lea that he doesn't take it seriously, but his friend is fairly certain that Isa believes more than he lets on. His interest originates from his parents pushing him to study astronomy, a subject that would surely get him a job working for Ansem and his team of brilliant scientists. Isa's parents never learn about their sons fascination. He's not entirely sure they would approve, and besides, he likes having something to secretly call his own. Plus, him and Lea conning people into paying for readings is probably illegal in some way, and they need ice cream money. He's a cat person. Lea regularly takes him for ice cream. Isa isn't really that fond of it, or eating anything very cold. He's just humoring Lea. That, and he really likes sitting on top of the fountains as the sun sets. (Bonus points if he can jump down into the pools afterwards on hot days... or push Lea in.) His diet is in complete contrast with Lea's. Healthy foods. Foods for necessary weight gain, heart health, brain growth, and so on. (While Lea always seems to be trying to get him to eat junk foods that hardly resemble anything edible.) His room is kept obsessively tidy, but only because he's fixated on making sure that every part of it can be used to express himself nonverbally. Glow in the dark stars cover the room from wall to wall in carefully constructed constellations for the nights where he can't see the stars. A mobile hangs in one corner, and a telescope sits close to his window that overlooks the town below (though it only sits in his room because Lea uses it to investigate the castle). The only other thing that isn't really "his" are the castle plans pinned crudely to the wall furthest from his desk. Invading the castle isn't his idea. It never was. He really doesn't want any part of it... or at least that's what he says. The blueprints for what him and Lea know of the castle's interior are smeared with erase marks. They've been refining them for AGES. Parts Isa is worried his parents will see are covered by posters. Former plans left at Lea's house were destroyed by his parents because the two know well enough what their rambunctious son is up to. Isa has his mother's hair, and is absolutely more attached to her than he is his father. Lea teases him for it until he sees her chasing off their rival group one day after school. He's certain that's where Isa gets all his pent up aggression from too. Isa’s good at concealing stress. So much so that people don’t notice how uncomfortable he is in big crowds. Lea notices though. Head ducking, hiding in homework, and subtle changes in expression usually leave the red head doing what he can to keep people from bothering his friend too much. The effort does not go unnoticed. Isa’s always sure to thank him when they leave parties.