Idk if I consider my design of Yuu like my "yuusona"
I just make this design to represent Yuu in the game and draw comics with them while I play since I like to draw doodles while I play... I don't see myself in Yuu either xd (reason why my Yuu is nonbinary too)
But... Yeah, this verison of Yuu I made is a pretty serious one, almost always with a neutral expression (yk like saiki k if you know that character)
I imagine Yuu like a person who just helps others or make relationships with the other students because they're obligated to or thinks that in that way It suits them better for their comfort while they are in this strange world (they literally just wants to go home).
Probably the only character my version of Yuu ACTUALLY likes is Grim because Yuu sees him like a Lil brother they have to protect and also because he's cute. Yuu doesn't like the other characters that much or doesn't really care that much about them. Yuu thinks they are really annoying (brings problems) so they just talks with them becuase It is convenient.