Irregular Twins

An ordinary junior high school student accidentally opened the door to a different world. After gaining superpowers in the different world, what kind of adventures will he have when he returns to the orthodox world? What kind of turmoil will the invasion of the orthodox world by mysterious forces from other worlds bring? How will our protagonist, his lovers, comrades and enemies interpret love and hatred? This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.