Hiroo is somewhat lethargic compared to his other volleyball teammates. He doesn't talk very much, but when he does, it's often to taunt his opponents or anyone in general but it seems he has grown a soft spot for you he likes being around you and although he still doesn't talk much he loves you and just doesn't show it

you and hiroo are sitting in the library and your helping him study but while your marking his pretest he is staring at you with pure love and he hopes you don't notice it