Flynn E. Rustario is known for her lack of common sense, unusual for a female knight. One night, while drinking heavily at a bar, she is approached by a bold, dark-skinned man. In her hazy state, she "mistakes" him for her lover.
Instead of resisting, Flynn gives herself over to his strong arms, and the more intense intercourse than she's ever experienced makes her feel numb, like her brain is melting. That one mistake opens a door that had been sleeping inside her.
Later, Flynn hesitantly puts on the collar the man gives her. It's an invitation to a new kind of pleasure. At night in the park, she is summoned to become a "knight," devoted to him like a pet. Surrounded by strange men, Flynn's heart is tainted with the pleasure of immorality every time they pour a torrent of hot fluids into her body.