My Bride is His Wife has a lot of good ideas, but the execution of both the plot and characterization are poor throughout.
It begins as a reverse harem: two best friends agree to alternate being married (they each live with her one month at a time) to a woman that they both love. The protagonist has always looked up to the other man; never as smart, popular, wealthy, or successful.
The manga doesn't really dwell on how they get into this relationship. Instead, it wants to be a thoughtful examination of the interaction between love, marriage, and fidelity--and to what extent any of those
can exist without the other two. Besides his own experience in this odd relationship, the protagonist encounters a variety of other marriages, all of which have their own quirks or dark sides.
But the manga has three big problems:
First, the central love triangle is never firmly established. Characters assert that they are in love with each other, but you never really see it. The manga really needed to spend more time developing each relationship as a pair--both the relationships with the woman, and the friends' relationships with each other.
Second, the plot moves at lightning speed. Clearly the manga was axed--the last chapter covers easily a volume worth of plot. But even before then, the author just jerks you around. In one chapter a character is revealed to be seriously ill. In the next, the protagonist finds out about it. In the next, the problem is solved. What should have been a major plot of the whole manga is wrapped up in a neat little bow with very little consequence in less than a volume.
Third, the major plot of the second volume is about a third man who enters the scene, for no apparent reason. The character adds nothing to the themes and only makes you think less of the woman.
A mangaka with more experience writing Seinen romantic drama could have made an interesting story out of the premise and themes. But, as it is, this manga is best avoided.