In the 8th and final year of the gameafter the second semester, Kenichi may propose to your daughter while they are on a date. In order for this to happen, Kenichi's orb level must be at its absolute highest and Kenishi's friendship event must've occoured. Also, you must not have triggered any other endings. If you accept the proposal , the two will marry at the end of the game.
There are two different endings that one can achieve when marrying Kenichi, a good one and a bad one. One achieves the good ending by having low independence (under -80), and the bad ending by having high independence (over -80).
It is in this ending that you discover that Emily became a Newspaper Reporter, Hiroko is a kindergarden teacher, and Miho is getting married, Kuroda is working as a secuity guard and married with three kids.
In the end, you also discover that your daughter is pregnant.
Your daughter is fed up with Kenichi never being home and considers him to be irresponsible. They get into a heated argument since your daughter does not believe that Kenichi is helping her enough in the house and prioritizes his work over her and their home, this argument causes her to leave and file a divorce with him the next day.