My beloved stepsister, who raised me, was slept with by my worst friend… Wing Dance JUQ-568

Mai and I aren't actually siblings. During my school years, Mai was the stepdaughter of my mother's second husband. After my parents fell ill, Mai took on the role of both parents. As we spent more time together, I gradually developed feelings for Mai. One day, at a cultural festival meeting, I invited my classmate Yuzuru to my house. Yuzuru seemed interested in Mai, whom he had just met, and from that day on, he frequently came to my house…