My arrogant girlfriend's younger sister is so sweet and affectionate towards me!? Even with my girlfriend right beside me, my little devil sister is still relentlessly teasing me. (Miya Nanazawa, MIDE-658)

My girlfriend's younger sister has been seducing me lately, it's hard to resist... She hides her underwear from my girlfriend and lets him touch her... When we're alone, she acts all coquettish, secretly opening her private parts for me to penetrate...