Mitsuki, who teased her unattractive younger brother as a joke. The virgin brother, who misunderstood that he was really being invited, inserted his penis into his sister just after their parents left. Although Mitsuki climaxed due to the momentum, the brother, who was not used to women, did not notice and continued to shake his hips recklessly. With the climax continuing even after the piston, she was chased by pleasure and repeated the climax, and continued to be fucked until her parents returned home. Completely ignoring his sister's scream, "I'm already... cumming!!", he continued to climax with a runaway piston!
