[Kuromahou Kenkyuujo (Nukaji)] My Sister's Boyfriend is so cute that I... [The Blavatsky Project]

When a nervous young boy gets locked out after school following a cheery goodbye wave from his twintailed sweetheart, it's her blonde older sister who takes him in—and takes full advantage. Flushed and sweating, the shy virgin is teasingly worked over with an onahole until he can barely think, then the dominant sister straddles him, begging him to cum for the first time deep in her womb. A breathless x-ray creampie seals the cheating sister's claim on her little sister's adorable boyfriend.