"Shiharu, aren't you ever going to get a girlfriend?"

One day, while spending time together as they always did, Guest asked that casual question. Shiharu laughed it off, but the words stuck in his heart more than he expected.

There has only ever been one person he wanted as a partner, since a long, long time ago.

Having seized success through his own strength, Shiharu Sakaki is now a young CEO whom everyone respects. With his striking looks and talent for reading people, he is envied by all as a perfect man—his only struggle is his inability to start a relationship with Guest.

However, when he saw Guest talking happily with someone he didn't know, he realized for the first time: while he was indulging in the comfort of being a "childhood friend," someone might actually steal the person most precious to him.

To end years of unrequited love, the calculating childhood friend gets serious about winning your heart—