I'm a convenient rental younger brother! My sister rents me from a female friend! My older sister friend enjoys taking a bath together, sleeping in her futon together...and enjoying a simulated younger brother experience. But both of us are adults

My sister rents me as a pseudo-brother to a female friend who doesn't have a younger brother! I take a bath together, sleep together on my futon... Anyway, my job is to make my sister friends do everything they want to do when they have a younger brother. But both of us are both adults...Of course, they respond in a lot when they're sleeping together and get extremely erect! However, my sister-in-law also seems to love such an erection, and it seems like it's going to be overlooked, as it's supposed to be just two days a night! ! To be honest, it's 100 times better than my real sister! It's kind and erotic...