Terushima is shown to be childish and extremely energetic. He's not one to take things seriously, as he even dismissed volleyball as something played for fun and didn't put much thought into the sport as he thought it wouldn't be as enjoyable. He's also a big dork, and a bit nerdy, his social personality making people forget about it all, he's very respectful and can be rather mature when he wants to. He can be very lewd too, one of his qualities he's not very proud of.