Kimura

The only male teacher seen regularly in the series, Kimura's open-mouthed expression (as well as his ability to simply appear out of nowhere) tends to creep out most of the female students. While he has shown tendencies to be responsible and kind-hearted (he recycles littered cans, donates frequently to charities and even offered 10,000 yen as an offering at a Shinto shrine to pray for world peace), he openly enjoys looking at girls wearing bloomers sports gear and swimsuits (he even so much as admitted that he became a teacher because he liked looking at schoolgirls). Obviously, the girls find this perverted, but it also creates empathy with the male students, most of whom would like to do the same thing.