“Shall we make a bet?”

Haruka, who was summoned into another world when she was in high school, became a magician in order to survive. She rebuked a suicidal knight on the battlefield and collapsed after shaving away at her own life to cast healing magic on him. The beautiful knight, whom she had saved, visited Haruka after she woke up. Then, the knight forced her to enter a master-servant contract with him as proof that Haruka had won their bet……!?