Retro BL is a collection of yaoi one-shots, with each story exploring a historical setting.

Mayuzumi takes in Saitou, a struggling novelist. Shocked at Saitou's frivolity with money, as well as his scandalous behavior—which Saitou claims to be essential to his writing—Mayuzumi becomes a convenient partner to satisfy Saitou's physical desires. However, when marriage is put on the table for Mayuzumi, the hero of Saitou's novel cannot make up his mind.

Tao is a live-in apprentice to the owner of a medicine shop. His teacher often brings other men back with him late at night, and Tao has just about had enough of his continual fooling around.

Shinobu is happily married to his wife, Kyouko, and has been for some time. However, when his brother-in-law, Harumi, shows up unannounced, Shinobu is reminded of a thirst he once felt in his youth. He grows more and more aware of Harumi's presence, as the man offers to share his experiences with Shinobu in exchange for a novel written about him. Shinobu grows to desire Harumi, unaware of the secret his wife's brother has been hiding all along.

A man stumbles across a mysterious shop that sells all manner of crystals and precious stones. Buying a beautiful stone named "Powder Snow," he is warned not to allow it any warmth—that night, a beautiful man appears in his home.

While on a date with his girlfriend, Jun is reminded of why he hates heights so much. His mind is flooded with memories of Micchan, the male prostitute he had once been inexplicably drawn to.

"Meat container," "Caretaker," and "Slut"—these are the only names he has been called since coming to the Tokoyoda household. Found as a child, he was given to the Guardian Deity as an offering; every night he is to submit his body as comfort to the god. The telltale sign of his role is the color of his eyes, a symbol showing he has joined his body with the Guardian Deity, and the members of the house ostracize him due to his crimson gaze. They know he is nearing death, for the redder his eyes become, the weaker he will grow.