Ishikawa-sensei

Ishikawa-sensei is a teacher found alongside the 5th Grade teachers, most likely the gym teacher for that grade. Consistently running around in a jumpsuit and with his messy hair, beard and glasses, he occasionally assists in the issuance of advice and known spiritual information out of what he has known and experienced; however, he is also somewhat of a bad influence himself, known for keeping cards for various porn shops in his jumpsuit. (As Nube accidentally discovers one time when they fall out of a borrowed suit.) Although it is unknown whether or not he really is a 5th Grade teacher, Ishikawa-sensei is commonly seen alongside the 5th Grade teachers, thus his inclusion here. He also has a tendency of avoiding showers up to more than a month, and has a fetish for wearing women's undergarment, which turned out working against Nube when Minki, the sister of the Oni no Te (Baki) comes from hell to reclaim them.

(Source: Wikipedia)