In this world, there are heroes and magical girls. They are beings who contract with spirits to defeat creatures called Phantoms, which steal people's negative energy.

The protagonist, a boy named Kisaragi Kurona, is also one such being who defeats Phantoms.

However, the power Kurona possesses is not that of the heroes boys typically admire. So what is it?

Surprisingly, the form Kurona takes when manifesting his power is that of a magical girl—the complete opposite of a boy's dream and his own gender.

Kurona chose to be a magical girl for only one reason: his younger sister loved magical girls.

(The main story has concluded! Thank you for your support!)

An edited and revised version has been posted on Kakuyomu. This version remains as is, as I wish to preserve the original text.