Elf no Kuni no Kyuutei Madoushi ni Nareta no de Hime-sama ni Seiteki na Itazura o Shite Mita

Through a series of coincidences and misunderstandings, Keith (the protagonist) becomes a hero in the elven realm, which has little to do with humans, and is quickly appointed as a court mage.

The king, who sees Keith as a talented man, asks him to teach magic to his daughter, Naia, a princess who was born unable to use magic.

Naia is a lovely only daughter who is loved by everyone, and she grows increasingly fond of Keith, the hero.
Naturally, she has no doubts!
Keith does everything he can to make her learn to "cum" while pretending it is a cure, even blindfolding her with her twin-tail hair and making her suck his cock.
He even makes the innocent princess scream lewd words and film herself being fucked!
She doesn't think it's naughty at all, but she grows up to be his ideal slutty princess bitch.

And Aisha, the escort knight, who has discovered the princess's lasciviousness, makes a promise to Keith in order to protect Naia...