Masami Yamada
A quiet and shaggy male teacher whose hobby is creating human-powered planes. At first he appears to be something of a physically-developed nerd, obsessed with his hobby. Koishi delivers him meals from her parents' grocery store. He later becomes something of a confidant, attempting to help Koishi by providing a sympathetic ear after a breakup with Kei and her subsequent depression but does not take advantage of her vulnerable situation. At the end of the series, it is implied that their relationship gets much closer than that of teacher and student