どうやら俺は今どきギャルな歳上幼馴染から激重感情を向けられているらしい

The protagonist, Kujou Yuito, has always struggled with self-confidence. A major reason for this is the overwhelming presence of his twin brother, Kujou Ayato, who is practically a superior version of himself in every way.

Adding to Yuito’s feelings of inferiority is the fact that his first love—and the girl he still has feelings for—his childhood friend of the same age, Yuuki Suzuno, is in love with Ayato instead of him.

That’s why Yuito has no idea that Suzuno’s older sister and their older childhood friend, Yuuki Natsuno, actually harbors intense feelings for him.

This is the story of how Yuito, who once thought of himself as nothing more than a “cheap knockoff” of his twin brother, begins to realize his own value and appeal through the efforts of the modern-day gal, Natsuno, and starts changing for the better.