Kugayama-kun ga Asa made Hanashite Kuremasen! Toshishita Kare to no Himitsu no Shinkon Seikatsu

Workaholic Ai Suruga and her junior Yu Kugayama are hiding a secret from everyone else—they're actually married! With how quick their friendship blossomed into love, it's no wonder no one believes such a young husband's love could ever run true - including Ai herself.

(Source: Fantasista Inc.)