A completely subjective drama in which Fitch exclusive Reina Momozono passionately plays the role of a big-breasted sister who loves her brother too much! Since she was little, Reina is a younger sister who has been so secretive that she has openly declared to everyone around her, ``I'll definitely marry my brother in the future!'' However, she was quite shocked when she found out that I was her first girlfriend... I decided to introduce her to her parents during the upcoming holiday, but I ended up separating my relationship with her.