Well, it's mainly about a girl's journey in a marriage. She might face various challenges and also experience some heart - warming moments. But to know the exact plot, one really needs to read the novel.
I'm not sure exactly who the main characters are without reading it, but I assume they are the same couple from the first volume who are working on their marriage.
It could be the way the story is told. The author may use a special narrative style in 'My Happy Marriage Vol 4'. The details of the setting, the dialogue between the characters, and how the emotions are conveyed can all contribute to making it a special addition to the series. Maybe it dives deeper into the cultural context that gives the story a unique flavor.
Midoriya Izuku is surely an important character. His journey to become a great hero continues in this volume, and we might see him develop new skills related to his One For All quirk.
One key feature is the further development of the characters. It might explore the backstories and growth of some of the minor characters. For example, it could show how they train and overcome their insecurities in a more detailed way compared to the manga or anime.
The full text of the first chapter of childhood is as follows:
chapter one
childhood
When I was a child, I lived in a beautiful village. The people there were very friendly and peaceful. I like it there so much that I visit my family and friends every day.
One day, I decided to go on an adventure. I brought my toys and snacks to a dense forest. I wanted to see if there was anything interesting there.
I walked along a path for a while when I heard a scream. I turned around and saw a squirrel being chased by a big bear. I wanted to help the squirrel, so I ran to the bear.
I chased the bear away. The little squirrel thanked me gratefully and I felt very happy. From that day on, I decided to be braver and help those in need.
This was my childhood, a story full of adventure and fun.