Tachibana Fusai no Kakushigoto na Shinkon Seikatsu

Keita and Mio Tachibana are a newlywed couple. The two met at an arranged marriage meeting, but they both have a secret that they don't want each other to know. That secret is that in order to impress Mio, Keita plays the role of the hero from Mio's favorite shojo manga, and Mio pretends not to notice, but she knows all about it. Nothing happens, but it's still fun. What kind of laid-back and sometimes heart-fluttering newlywed life will the two of them lead?

(Source: Comic Days, translated)