Nanako Mizuki

She appears in first episode, at the very start of GTO series and is Onizuka's next big challenge at Musashino. She lured him into a trap in an attempt to try to get some money out of him (along with the 3 punks of Class O), but Onizuka didn't go down. At around the same time, she tried to reach out and get some help. With her family life deteriorating, she felt that Onizuka could fill that void. Ultimately, Onizuka did something to help her out, demonstrating his abnormal strength by destroying a part of wall which was to symbolize the distance she was feeling between her and her family.