My Wife Might Be a Hentai.

For some reason, Hiroki Shindo is getting married to his childhood friend Ryoka Mita. Since it is not a love marriage, they were supposed to remain just friends even though they became husband and wife. Once they move in together, however, Ryoka's true nature is revealed! A life of being loved by a slightly perverted wife is about to begin!

(Source: Kadokawa, translated)

Note: Includes three extra chapters.