I succumbed to my sister's unguarded seduction; after trying sex, I instantly became erotic! Every day, I'm irresistibly aroused by my sister's relentless seduction. (Igarashi Natsu FSDSS-492)

My parents remarried, and I gained an older sister. She's a stunningly beautiful, aloof woman who always lounges on the sofa without any defenses. One day, I finally couldn't resist and directly inserted my penis into her beautiful buttocks, then vigorously thrust and ejaculated inside her…