Keeping a Low Profile at Hogwarts to Become a Magical Girl

Casey had no objections to awakening the power of a magical girl. Although he was a boy, there had been male predecessors before him. Casey also had no problem with magic existing in the world. As someone who had transmigrated, that was only natural. But transmigrating into the world of Harry Potter and awakening as a magical girl? Wasn't that a bit too incongruous? Worse still, Dumbledore witnessed the whole thing: Casey transformed into a magical girl, defeated a monster, and turned back into a boy! Dumbledore: You can choose the boys' dormitory, or pay a small price to choose the girls' dormitory. Casey: Yang or yin, that is the question. Magical girls are the embodiment of love and justice! But they also need friendship and bonds, and young witches and wizards are never short on curiosity. Professor Dumbledore didn't mind Casey spreading the magic of love and justice, either. And so Hogwarts gained a secret magical girl society. Until more and more young witches and wizards joined, along with Professor McGonagall and Professor Sprout, and even... Grindelwald? When the Dark Lord Voldemort returned: Why do you all have a second stage?! And why are you all magical girls? When magical girls spread throughout the entire Wizarding World, he stood at their very summit. I, Casey, shall prove my magical-girl Dao and reign supreme throughout the ages of wizardkind!