Kageyama Shigeo is an average middle school boy, nicknamed Mobu (meaning “background character”) as he lacks a sense of presence. Although he looks like an inconspicuous person, he in fact has powerful psychic abilities. As he grows older, Mobu realizes his powers are strengthening and becoming more dangerous, so he suppresses them and keeps his emotions under tight rein. He wants to live a normal life and make friends, but trouble keeps coming after him. With his psychic mentor (who has no psychic powers), he continues his daily life, attempting to realize his purpose in life.