The protagonist is reborn into a fantasy world with adult intellect and overpowered magic, often shocking everyone with their talent despite being a "brat" or small child.
Kenji focuses on Aoi. In his original life, he joined in on light bullying to "fit in," which led to her moving away and eventually disappearing from his life. This time, he uses his adult emotional intelligence to defend her, becoming a social anchor for the "outcasts" in his class. gaki ni modotte yarinaoshi comic