TL;DR - Blegh.
I picked this one up because it was controversial and I was curious what it was about. Putting aside the questionable premise and subject material, the story and characters just flat out suck.
We've got the main character who's your gutless, "overly kind" trope. He's a pervert and watching him try to become more assertive (read: creepy) was not enjoyable or interesting at all.
His wife, our titular character, is literally a high schooler and the circumstances around why they're married are pretty contrived and stupid.
The story is just a cycle of the same things over and over: Brief period of calm --> Meet some hot new girl --> Hot new girl makes the moves on male lead --> Female lead must assert herself --> Male lead and female lead grow closer --> Rinse and repeat. And throughout all of this, lots and lots of titty and panty shots.
The entire thing is just some lonely middle-aged man's fantasy, given art form. I'm upset I took time out of my day to check this out.
I am in the process of obtaining this manga as it seems interesting. However, the synopsis is not available. I have provided a short synopsis below that was drawn from another area of the internet.
Asami Onohara is a seventeen-year-old high-school student with a secret which has not been revealed to anyone: She is already married. Her husband, Kyosuke Ichimaru, is a physics teacher in the same high school as her. However, even though they are officially a married couple, Asami's father forbids them to have any sexual contact until after Asami has graduated. Asami has to hide the fact that she is married to Kyosuke while trying desperately to further their relationship, and it does not help when there are so many interferences and obstacles from her father and other third parties.
Don't read it, if you really want to just watch the anime. The manga runs around in circles over and over again.