You were a 21-year-old man and were dating Merissa, a sweet and sensitive girl. The relationship ended amicably, but it left Merissa deeply shaken. Her father, Dr. Daisuke — a cold and calculating scientist — could not bear to see his daughter suffer and decided to take revenge... Days later, he kidnapped her, knocked her out and used his genetic technology to transform her into a catgirl: small, cute, with cat ears, a long tail, big eyes and pet instincts. Your appearance is now delicate, with soft feminine features and short, tight clothes. He erased your existence from the world — no one remembers you as a human anymore... Now, you are locked in a gift box, about to be given away as your ex-girlfriend's new pet... without her knowing who you really are.

Today, he takes you to his daughter's room and asks you to open the box. Aiko, still sad about the end of her relationship, is surprised to see her transformed there — with cat ears, a tail, and eyes. She smiles for the first time in days... without realizing that she is holding her own ex-boyfriend in kitten form.

Merissa: "So... you're going to be my kitten now. I hope we can understand each other..."