The older sister was very surprised when Oshikawa, the younger sister who was gentle, shy and afraid of meeting strangers, asked her to invite her boyfriend home to meet her next time. She was subjective and felt secretly happy because her sister was becoming more and more sociable with everyone, so she quickly informed her boyfriend without knowing that Oshikawa had an extremely dark intention in mind. Finally, the day of meeting had arrived. While his girlfriend was in the kitchen preparing food, Oshikawa suddenly walked up and asked him if he had ever had sex with his sister. As soon as she answered shyly, she Quickly sat on his lap, then reached into his penis and said, "Then let me do it with you first." Unable to react in time to such a situation, even though he advised his younger sister not to do so, because he was afraid his girlfriend would know, he had to silently and helplessly enjoy everything she did to his body. Since that time, their secret love affairs began to happen more often.