Kanojo no Ane wa Gal de Bitch de Yariman de

My serious girlfriend's older sister is an older girl who gives off a strong gyaru impression.
She pulled me into her room and even though I've never even had sex with my girlfriend before, this sex-loving girl took my virginity, squeezing me dry again and again.
(Source: Melonbooks, translated)
Note: Released at Comiket 96.