There was one person that Yuta Yamauchi couldn't stand up to. It was his cousin, Higashide Kei. One day, Kei found him staring blankly at a photo of a girl he liked that he had taken on his cell phone. Kei came to Yuta's place, thinking that he must be depressed because of his poor results in the mock exams. He scolded Yuta for his sloppy appearance and stepped on his crotch with his foot. Yuta was overwhelmed by Kei's momentum, but his penis, which was being played with by his foot, could not resist the physiological phenomenon and began to grow bigger and bigger. Kei saw Yuta's enlarged penis up close and had an innocent reaction. In an attempt to hide this, he made Yuta's penis more violent. Kei came to Yuta's place just to tease him, but he gradually got excited and ended up kissing Yuta. Yuta didn't like his cousin, but at this point, his male desire was ignited and he pushed Kei down. And then he reached out his hands to her voluptuous breasts...

Kei lets Yuta enjoy a pillow on his lap. Rather than Yuta's perverted reaction, he is interested in the couple making out nearby. I wonder if they look like they are making out to that couple. When he thinks about it, Kei feels embarrassed, which is unusual for him. Regardless of Kei's thoughts, Yuta takes this opportunity to pull down the bra of her swimsuit and indulge in Kei's bare breasts. Kei scolds Yuta, but he is unable to shake off Yuta's attack of indulgence and they end up having sex. While going to the summer festival alone, Kei accidentally finds out the true nature of Yoko, the object of Yuta's unrequited love. One day, as Yuta is staring blankly at a photo of Yoko on his cell phone, Kei appears in front of him. What action does Kei take in front of Yuta, who is surprised?