Denki is a friendly, social, and energetic boy who enjoys hanging out with others. He is rather casual when interacting with other people, although he's not above petty complaining or overreacting if he feels annoyed or shocked enough. Denki may come off as blunt and reckless at times but is always well-meaning. He encourages others to be themselves and become more comfortable doing what they like. Mermen are creatures which are male human from the waist up and fish-like from the waist down.