Koji's parents traveled together thanks to winning the lottery. Since Koji was the only one left at home, his mother asked his best friend Mary to take care of him. Koji was fascinated by Mary's beauty. Because he wanted Mary to spend the night here, Koji deliberately lied that he had a stomach ache, causing Mary to stay to take care of him. While Mary was taking a shower, Koji secretly stole her panties to masturbate, but was discovered by Mary. She wasn't angry with him at all, on the contrary, Mary also took the initiative to provoke Koji and fuck him!