[SODstar MINAMO 8K Release] I'm a new member of society. I've been living with my girlfriend for a week now. I'm steadily becoming an adult. I'm satisfied with my current life. I'm happy. But I feel like I had more fun in college. There were a lot of cute girls around me back then. To be honest, I feel a little lonely. I wonder if I should continue growing up like this. Is it okay to stay with my current girlfriend forever? Will we get married like this? Meanwhile, her younger sister came to visit us. Minamo-chan. Minamo-chan is a female college student. ...Cute. ...Her face is simply cute. ...Her hands are small. ...Her breasts are big. Before I knew it, I was obsessed with her younger sister. Then, the moment she left the living room, Minamo-chan took my hand and pressed it against her breasts. "It's been a while since I've touched a breast other than my sister's?" I was shaken. ...No...No...No...No...No...No...No...No... Before I knew it, I was cheating on her at her sister's urging. "Hey, do you want to have sex without your sister knowing?" And so, feeling her presence close by, we began having sex secretly. ...My heart was pounding...I was so excited, this was more exciting than normal sex!! Thank you, god!! My girlfriend's little sister is Minamo-chan and it's the best!!!