ECBM-010 His stepsister is so cute that his brother keeps having sex with her and taking pictures of her every night, but when she comes home drunk, he mistakes her for his boyfriend? Forbidden, sweet, and romantic sex with penetration!? Yui Tenma - Tenma Yui

When Reiya and Yui's parents remarried, they became step-siblings. Their relationship was good, without arguments, but Reiya's feelings were somewhat twisted; he broke into Yui's bedroom one night and raped her… One day, Yui went on a date with her boyfriend and came home drunk. Yui mistook Reiya, who was taking care of her wholeheartedly, for her boyfriend and began an intimate relationship with him, eventually even performing oral sex on him. Reiya was powerless to resist, and the two finally crossed the final line, ejaculating inside each other.