A girl whom Kanta tried to save, she is very easy-going. She wanted to meet her father no matter what, but her mother is so overprotective of her that she forbid her to meet him and even chauffer couldn't bring her to the house of her father. She made an agreement with chauffer that she will find a boy who could save her from fake kidnapping so that she could visit her father during that time.
One of Makoto's work colleagues. Not married. Envies Makoto because of the beautiful wife he has. As well as Okahama sometimes acts like a pervert. Is not really attentive to his sex partners (which is discovered during the girls' talk about the worst types of men).
One of Makoto's work colleagues. Not married. Has many fantasies about women and often says vulgar things making Makoto blush. Okahama himself thought he was good at sex until girl colleagues started to discuss the types of men they hated most. Then it revealed that he had a lot of problems, f.e. thought only about himself.
Makoto's father. A 52-year-old company officer. He is overly sensitive about his sex life, and far too protective of his youngest child, Jun. (source: http://en.wikipedia.org/wiki/Futari_Ecchi)
Makoto's elder brother. A 29-year-old lawyer. He is very nosy and frequently pesters Makoto about his sex life and fancies himself as Makoto's tutor on the topic of pleasuring women. In order to appease his own sex drive, he frequently visits brothels. Is used to speak in an extremely loud voice which (along with the topic Akira usually covers) makes everyone embarrassed.
A male bear. Kumakichi is Usami-chan's classmate, who will more often than not be the culprit in the cases Usami-chan solves. (Source: Wikipedia)