SNIS-397 I'm going to get raped. ~An older sister who loved her younger brother~ Tenshi Moe

An angel goes to rape himself...The price he pays for protecting his younger brother's life is an angel's body. She is stripped naked at the will of a man who enjoys perverted tastes, tied up with hemp rope, and teased while her own masochist awakens. As he was writhing and losing himself in the pleasure of being humiliated, his younger brother Yuta appeared in front of him... and was raped in front of his younger brother...? No, a reality even more outrageous than that attacks Moe.