Dangerous Relationship with Girlfriend's Sister - Haruna Osaka IPZ-494

Haruna, with her innocent smile and straightforward eyes, is my girlfriend's older sister! I've completely fallen for Haruna, beginning this dangerous and secret relationship! Although I know this twisted relationship can't last, I've stopped lying to my feelings! What will be the outcome of my secret relationship with my girlfriend's sister...? The role of my girlfriend is played by popular actress Riku Minato! Of course, we'll also have sex!