Deisui Shite Osotta no wa Suki na Hito no Otouto Deshita.

When Akira receives a marriage announcement from his first love, the crushing weight of despair drives him to drink. In his intoxicated state, he makes a reckless and irreversible decision, forcing himself upon Haruto, his first love’s younger brother. Over the following years, Haruto grows to strikingly resemble his older sibling, prompting Akira to keep his distance. He is terrified of developing inappropriate feelings for the young man, yet despite his best efforts to stay away, those very emotions begin to take root. Plagued by guilt, Akira fears he permanently scarred Haruto, who has always shown him nothing but genuine kindness and care. However, Haruto shatters those assumptions with a single, possessive demand: “Don’t act like that in front of anyone but me.” Following their one disastrous night together, Haruto suddenly begins behaving as though they are already a couple. Radiating unexpected cheerfulness, he actively pursues Akira, who is left bewildered but ultimately allows himself to be swept along. What was never meant to become serious gradually transforms into something profound. As Akira witnesses Haruto’s unwavering and admirable devotion, the younger man becomes increasingly precious to him, turning a moment of drunken regret into an undeniable bond.