(from ebookjapan):
Kyoto in 1862, near the dawn of Japan. There was a boy who repeatedly exploded after a failed experiment. His name was Moichi. He had no relatives and was being taken care of by a monk at Iboji Temple. One day, Moichi meets Ryoma Sakamoto of the Kaientai, who is hiding in the temple. He was wounded and said that he was being chased by the Shinsengumi. In order to escape Ryoma from the temple, which is surrounded by the Shinsengumi, Moichi creates a new invention. ......!?