Shinichi Kirishima
Shinichi is Samatarou's and Tenko's friend at school. He's quite girl-crazy and frequently peppers his speech with English phrases when he becomes excited - which he often does, especially when talking about girls. His friends consider him something of an idiot, sadly not without reason, but he seems to be essentially good-natured. Eventually, Shinichi manages to develop a romantic relationship with Ai Tachibana, much to the horror of Samatarou and Tenko. Despite their feeling of foreboding and Ai's occasional displeasure, Shinichi is apparently true to the relationship.