One Piece: Possessed Teacher

Qin Tian traveled to the pirate world and obtained the Possession Teacher System, allowing him to possess the opposite sex and share their bodies. He possessed eight-year-old Nico Robin and raised a Thousand-Armed Ice Queen, who protected O'Hara! He possessed twelve-year-old Hancock and raised a Flame Dragon Princess, wielding dragon-slaying magic! He possessed ten-year-old Nami and raised a Weather Goddess, who presided over the Brilliant Sky Thunder Prison! ... After Qin Tian had trained ten qualified apprentices, he was finally able to reshape his physical body. Standing at the entrance to the Grand Line, Qin Tian declared to the world: "I will destroy Marijoa and reshape this world!" Thousand-Armed Ice Queen Robin: "I will freeze the entire world for you, Master!" Flame Dragon Princess Hancock: "I will burn everything for you, Master!" Weather Goddess Nami: "I will thunder with my might for you, Master!" Ocean Ruler Shirahoshi: "I will flood the Red Earth Continent for you, Master!" ... (This story and characters are purely fictional. Any similarities are purely coincidental. Please do not imitate.)