Uchi no Ko wa Mahou Shoujo ni Naranai

In this world, a mysterious monster called "Acrylamide" is threatening humanity after a meteorite crash. The only hope is a "magical girl" who can defeat Acrylamide! Akuto, whose sister is the magical girl Shiny, also known as Shiin, supports her efforts, but one day, she commits suicide after defeating Acrylamide. What will Aku do to get his sister back?! A time-traveling comic about a sister complex and an illegal magical girl!