Gonna point out one detail we are conveniently overlooking - Midori is, by any normal standard, cheating, while as far as we know Tazune is not (yet, though obviously thinking of it). Knowing Tazune is abusive, knowing the pregnancy is due to him just deciding he wanted to go in raw and nakadashi, and of course being on this site we aren't going to care much. From a perspective of ignorance, though, it looks flipped from what we see.
In any case it's obvious they aren't really into each other and both are more in for something on the side, so maybe, just maybe they should not get married?
I hope the new girl helps Maki and Midori get knocked out of the mental trap that keeps them from acknowledging that they are a couple already, obviously want to be together, and Tazune isn't committed to the relationship either so BAIL NOW!
I just know the damn pregnancy is going to make this shitty and complicated. If there is a fight over custody, once again, there is proof Midori is cheating and with a woman at that, while no one but us and Midori knows Tazune is an abusive dick. Best case, it doesn't come down to that, Maki and Midori get together and raise the child. Worst case, lots of drawn out drama.