Onsen-Mark

温泉マーク

aka Onsen Mark

One of Ataru's teachers. A sad, middle-aged man, whose only interest is to teach at Tomobiki High, but fails due to the constant interruptions during class, when the classroom itself is not destroyed by Lum, Ten or Shinobu. His name means "Mark of the Hot Springs", and he usually wears a shirt with hot springs on it.