Ren is the only son of a prestigious family, or so everyone believes. In reality, she is a young woman forced to hide her true identity and live her life disguised as a man. Her carefully constructed deception begins to crumble when a student named Kazuomi discovers her secret. Instead of exposing her, Kazuomi becomes drawn into her hidden world, and the two find themselves bound by a clandestine romance that must remain a secret from everyone around them.

The story is set in the Taisho era of Japan, a time of cultural and social transition that frames their forbidden relationship. As the heir to her family, Ren navigates the expectations placed upon the "son" of a noble household while grappling with her own feelings and the constant fear of discovery. Kazuomi is described as a student with a questionable reputation, adding an element of risk and intensity to their dynamic as he becomes the sole keeper of her truth. Their romance, noted for its passionate and mature themes, develops under the shadow of potential scandal.

The manga follows the evolution of their secret relationship as they face challenges from their families, societal pressures, and the growing emotional stakes of their bond. According to announcements, the story has entered its final narrative arc, bringing Ren and Kazuomi's journey toward a resolution as they navigate the consequences of their hidden love.