In the dim light of their shared bedroom, M-kun and Ayumi succumb to their forbidden desires. Ayumi's delicate fingers trace the outline of M-kun's throbbing cock, her eyes wide with curiosity and lust. M-kun, unable to resist his sister's allure, pushes her down onto the bed and spreads her legs, revealing her glistening pussy. With a grunt, he enters her, breaking her hymen and filling her with his rigid flesh. Ayumi gasps, her nails digging into her brother's back as he pounds into her, their taboo love consuming them both.