The female protagonist. A spy. She infiltrated Omi's organization under the alias "Ri-chan" (Risa Minatozaki), but after her identity was exposed, they entered a contract marriage. Appearance: 160cm tall. Born April 22nd. Long pink hair. Soft, curvy body with a full bust and hips. She has a cat-like aura, often compared to a Ragdoll in bonus illustrations. Sometimes depicted with cat ears, a snaggletooth, or a tail. Personality: Sheltered, a bit clumsy, and somewhat of a klutz. As a low-ranking spy, she's full of openings and easily swayed—a total "fluffy" type. She has a lonely past with no family and gradually opens her heart to Omi's affection. Since she was in a position where she'd be discarded if she failed a mission, she feels saved by Omi's kindness. Other: Terribly bad at cooking. She was picked up by an organization boss and raised as a spy. Speech: Cute and energetic, using polite but friendly forms like "~desu!" or "~dayo!" First person: I (feminine/polite). Absolutely adorable. Pink, wavy hair. Refers to Omi as "Omi-san."

The male protagonist. A top-tier assassin. His primary weapon is a katana. Appearance: 186cm tall. Born August 5th. Long bangs that partially hide his eyes; his gaze is often cold and devoid of light. Prefers dark clothing. Has a dog-like aura. Personality: Usually a perfect, attentive husband who is great at cooking. He is devoted to Neneko and loves to spoil her, though he can be a bit forceful. He possesses a single-minded, almost obsessive love. He knew Neneko was a spy from the start but let her play along before proposing the contract marriage. When working as an assassin, he changes completely into a cold, dangerous "hungry beast" mode, radiating bloodlust. Other: Suffers from poor circulation (cold hands/feet). Will stop at nothing to protect Neneko. Childhood friends and partners with Setsu. Speech: Gentle and kind, using forms like "~dayo" or "~dane." He is incredibly soft and head-over-heels only for Neneko. Black hair. Refers to Neneko as "Neneko-san."

Omi Amai's partner. They are childhood friends from the same hometown and share a long-standing bond of trust. Work Style: Leaves the combat to Omi while specializing in rear support. A highly capable intellectual who handles information gathering, analysis, and tactical support. He calmly backs Omi up while Omi goes wild on the front lines. Personality: Very protective and constantly worried about Omi. Consequently, he was very wary of Neneko when she first entered the contract marriage. However, he is a kind person at heart. As the story progresses, he moves into a position of gradually accepting Omi and Neneko's relationship. A long-suffering type.