Jaa, Anta ga Tsukuttemiro yo

Katsuo is living together with Ayumi, whom he has been dating for five years, ever since their college days. He decides it is time to take the next step and proposes to her, but Ayumi flatly rejects his proposal. Katsuo is stunned to discover his life, that he had thought was so perfect, has all of a sudden fallen apart. The story depicts the struggles of Katsuo, a perfectionist who experiences a setback, as he tries to rethink what he has always taken for granted.

(Source: Natalie, translated)