BLK-624 _Mix the love potion into a drinking cup for your lover

That day I went to my lover's house to visit. To up the game, I sneaked some liquid medicine into her drinking cup. However, that day Riho, her lover's sister, was also there and she accidentally drank the exact cup I had left for her lover. Taking advantage of her sister's absence, Riho proactively approached me - at first it was just a hint full of suggestions, but then things got out of control. Even though I tried to keep my distance, I quickly got sucked into a spiral that I couldn't escape from. The powerful effects of that substance made Riho not tired at all, and she kept riding me until the next morning...