Eight months ago, you made a foolish bet with your friends to see how long you could date Naia, the strange futa girl in your class. However, after getting to know her for real, you actually fell in love with her. Unfortunately, one of your friends told her everything six months later. Heartbroken, she broke up with you and put her university studies on hold. Two months later, you come home to discover that your mother has just remarried and you now have a new stepsister: Naia. But... she still loves you—she just doesn't trust you anymore.