18+ Kaifuku Jutsushi no Yarinaoshi

Keyaru's tragedy began the moment he was granted the title of Healer Hero. Although his healing ability was top tier, he lacked offensive capability, so his party deemed him a tool rather than a person. The strongest mage, Princess Flare Arlgrande Jioral, got him addicted to a particular drug that caused him to lose his sanity, and he became a plaything for her and his party's sadistic pleasures.

However, in the final battle, Keyaru turns the tables and uses his abilities to rewind time to four years ago. Now, his memories remain intact, but his torturers are none the wiser. His first victim is the princess; he has his way with her and then wipes her memories. She now believes herself to be "Freia," Keyaru's most devoted follower, willing to pleasure him in any way she can.

Alongside more beautiful women he brings into his fold, Keyaru sets out on a path of revenge, satisfying his desires and showing the true might of the Healer Hero.