The Reason My Boyfriend Married My Older SisterTV Show

Aiko (Akita Shiori) is called to a hotel room by her ex-boyfriend, Yuma (Kageyama Takuya), who is now her sister Saeko's (Takada Riho) husband. For some reason, she meets Yuma's father, Masaki (Maruyama Tomoki) there, but suddenly loses consciousness. When she wakes up in bed in the morning, she finds Masaki sleeping half-naked next to her...! Aiko can't accept this reality, but later, while she is working at the apparel store where she works, Yuma's mother, Yuriko (Akama Mariko), appears and confronts her with a photo...! Furthermore, Aiko goes to see Masaki, who claims to know the person who pushed her down the stairs. But who is that culprit...? And what exactly are Yuma's true feelings...?!