University students Hayato and Jin have been close friends since childhood. When they move to Tokyo together, Hayato harbors a secret: he is gay and has been in love with Jin for years, knowing that Jin, who is straight, will never return his feelings. While searching for an apartment, they stumble upon a very cheap property with one unusual condition only married couples may live there. On the spot, Jin impulsively announces that they are a couple, and the two begin living together as fake newlyweds. Their deception soon faces a challenge when their landlady grows suspicious because she never hears any sounds from their apartment that would be expected from a newly married couple. In an attempt to sell the lie, Jin makes a shocking suggestion: they should pretend to be physically intimate, and he begins touching Hayato. As Jin initiates more of these acts under the guise of maintaining their cover, Hayato struggles with his genuine feelings and his body's honest reactions, finding it increasingly difficult to remain just a friend.

Tomodachi Engage is a Boys Love manga written and illustrated by Mochi Warabi. It was first published in Japan on June 16, 2023, by Suiseisha under their Glanz BL Comics imprint. The series is ongoing, with at least 32 volumes released as of late 2025. The story follows Jin, described as a handsome and straightforward straight man, and Hayato, a gentle gay man who hides his true feelings behind a sweet demeanor. The narrative focuses on their evolving fake relationship, from the absurd arrangement to the gradual blurring of lines between performance and genuine emotion. Key arcs of the story include the initial apartment search and the decision to lie, the escalating intimate acts designed to fool the landlady, and the internal conflict as Hayato begins to hope for a real relationship while fearing the inevitable end of their charade.