Wakeari Omega wa Nige no Itte

Childhood friends Shin (alpha) and Mahiro (omega) had a one-night stand when Mahiro went into heat. After that, Mahiro abruptly left university and disappeared. A few years later, the two met again by chance, and Shin mistook Mahiro for a prostitute. Shin told Mahiro, "I'll be your exclusive customer from now on." Mahiro couldn't refuse out of love...