Kenja no Mago SP: Oujo-sama Funtouki

"I also want to save the world!"
Princess May of the Earlshide Kingdom loves talking about her beloved Shin to her friends who attends the Primary School. She wants to fight with him. The people around her find May's remarks unbelievable, but she secretly learns attack magic from Alice Corner and Lynn Hughes
One daye, May, who participated in an open-air camp hosted by the school, is abducted by a teacher who has been brainwashed by a devil...
(Source: Kenja no Mago Wiki)