Dark sex-slave ● Lara Kudo.

Satoru-kun, whom I call big brother, is a childhood friend who is older than me. My older brother has always been good at studying, kind, and popular with girls... I've always had a faint crush on him, but he only thinks of me as his little sister... Such a big brother returned from studying abroad, and it was decided to meet again for the first time in six years.