I'm Giving the Disgraced Noble Lady I Rescued a Crash Course in Naughtiness 7 (manga)

After learning that Charlotte’s younger sister Natalia is in trouble, deviant sorcerer Allen and his crew set off to rescue her. Their destination: Athena Island, home to the Athena Magical Academy, where Allen grew up with his adoptive family. But figuring out what trouble a seven-year-old could’ve gotten into isn’t Allen’s only daunting task, as his first trip home in three years threatens to reignite an explosive argument he had with his father—one that forever changed the course of Allen’s life.