KNIP-008 My brother, who had zero knowledge about sex, got a girlfriend, and I realized my feelings. My sister teaches me a lesson on youthful creampie sex education. Mihiro Tanaka, explosive birth

Mihiro, the younger sister, finds out that her unpopular older brother has finally found a girlfriend. Unable to express her joy, Mihiro eventually realizes her own feelings... "I've always loved you, big brother..." The day before their da