MIAA-048 Her little sister tempts with full-force self-insertion

A man starts dating his childhood friend who isn't beautiful but has a good personality. When he visits her house after they start dating, her younger sister Shuri comes home. Unexpectedly grown into a beauty, she makes him flustered, but he keeps his composure and treats her like a child. Suddenly, Shuri says, 'I'm better at it,' forcibly removes his pants, and deep-throats him in a self-fellatio. Overwhelmed by the pleasure, he can't hold back and ejaculates down her throat, with saliva and semen dripping from her mouth!