This is a bizarre sex education Manga staged in a school, featuring a rowdy boy called Yakeppachi and a girl named Maria, who is the ectoplasm of Yakeppachi. Yakeno Yahachi, a rowdy boy known as "Yakeppachi" gives rise to a pretty girl named Maria while in a trance, and her personality is identical to Yakeppachi. Actually, she is the "ectoplasm" of Yakeppachi. "Ectoplasm" is a hazy stringy and fog-like substance that is generated from the spirit medium at a seance, also referred to as an "astral body." Taking on the form of a doll given to her by Yakeppachi's father, the ectoplasm Maria begins to go to school with Yakeppachi. The whole school is thrown into a state of confusion except the classroom teacher Akita, who is the only person to understand that this is a supernatural phenomenon. The plot thickens when, after finding out about the secret of Maria, a juvenile gang group ("Group of Tateyoko") that has been keeping an eye on Yakeppachi, start to follow him, thinking to stage a