We invited a pair of close-knit siblings who we picked up on the street to participate in an H project with a bounty! The younger brother, who shares a room with his sister, is surprisingly a virgin! His innocent brother is taught how to have sex by his older sister! If they can manage 'teasing,' they'll win the prize money. Although the sister is not particularly enthusiastic about the project, she reluctantly starts lecturing him, but gradually starts to feel good...
