HUNTB-380 "Big brother, let's drink together!" My little sister who just turned 20 becomes unexpectedly lustful on her first drinking experience! The innocent and serious little sister transforms into such a lewd woman when she's drunk...

My little sister turned 20 and consulted me, saying she wants to drink alcohol with me for the first time! What an amazing sister (tears). I eagerly taught her how to drink alcohol, but... hey? Something seems off? My usually shy sister gets a lewd look in her eyes when drunk and keeps insisting on my dick! Just as I thought things might be getting dangerous, she fully awakens into a slutty state!? She forcefully inserts it and even demands taboo internal ejaculation to the point of transformation! I intended to teach her how adults drink, but ended up teaching her how adults get fucked...