A Medium Voice.
Sakutaro is a character with layers: he likes to leave a good impression on other people, while hiding his inner personality. He acts calm, and takes situations, like Mayu's transfer, in his stride. Unlike the rest of the characters, he is neither disgusted nor horrified by the excessive gore and decaying corpses in Heavenly Host, instead he finds them intriguing and feels comfort in viewing them. However, he keeps this trait a secret from others. He is best friends with Mayu, and deeply cares for her, the one friend who would cheer him up when he is down. This is evident in that she is the only person who he lets give him a nickname.