The older sister was very surprised when Eimi - a younger sister who was originally gentle, shy, and afraid of strangers - asked her to invite her boyfriend to the house to meet them on the upcoming occasion. She was complacent and secretly happy that her sister was becoming more sociable with everyone, so she quickly informed her boyfriend without knowing that Eimi had a very dark intention in mind. Finally, the day of the meeting arrived, when the girlfriend was in the kitchen preparing food, Eimi suddenly approached and asked if he had ever had sex with her sister, as he was about to answer shyly, she quickly sat on his lap, reached into his pants and said, 'Then let me do that with you first.' Unable to react to such a situation, although he advised his younger sister not to do that, he remained silent and helpless, enjoying everything she did on his body. Since then, their secret affairs began to occur more frequently.