Maybe a Fake Gintama - Chapter 350: The So-Called Life Was Made of Constant Defeat!

Xiao Ze, who was dedicated to the people and vowed to become a generation of Ming Jun, accidentally fell on a little lady.
The little lady was born beautiful and lovable.
So Xiao Ze accepted his life and got the name of fear.

ps:
①The male protagonist has no concubine, and he is dedicated to serving the country.

- Description from novelbuddy

“There is a scar on my stomach which is hard to heal over the years”..

Ning Yu is forced to marry Song Bai Lao, whom he was deeply entangled as a teenager. Because of the misunderstanding they had before, Song Bai Lao keeps bad-mouthing Ning Yu to the point that he even becomes Ning Yu’s nightmare. As they get together, Song Bai Lao finally confronts his feelings for Ning Yu, and Ning Yu finally sees his true feelings and sincerity.

- Description from Novelupdates

It was supposed to be a perfect deal in which both parties got what they needed. However, after the child was born, he tore up the agreement with discontent and told her, “Who said that we’d only have one child? I want twins! Twin brother and sister! You’ll continue giving birth to more children until you bore me a pair of twins!”

Mu Zhiyan, after being transmigrated a millennium (1000 yrs) into the future, discovered that he was raised by his adoptive parents as a tool for them to access the heritage his (dead) biological parents left behind. When he was at a loss for what to do next, he discovered that his body hosted an additional
pharmaceutical system.

For a chance to return to his era of Earth, Mu Zhiyan decided to practice and practice; he must train the system to full level as soon as possible.

However, reality gave him a slap in the face. The world is dangerous and dreadful, making Mu Zhiyan recall his mother’s words of holding a thick thigh, resulting in him locking his eyes on a cool general…

So the rumored mysterious Mu Master faced General Han with a serious face: “I allow you to follow me, General Han.”

General Han: “…”

- Description from Novelupdates