I'll try to restate the point in my own words and see if that helps you.
"just world/character-building" would be if the plot was: a girl gets a soda from a soda machine, then take it to a boy. KishÅtenketsu is: a girl gets a soda from a soda machine. Meanwhile, a boy sits on a bench. The audience is confused at this point and that creates conflict in their mind. In the resolution, we see the girl was getting the soda for the boy.
"just world/character-building" would be if the plot was: a girl gets a soda from a soda machine, then take it to a boy. KishÅtenketsu is: a girl gets a soda from a soda machine. Meanwhile, a boy sits on a bench. The audience is confused at this point and that creates conflict in their mind. In the resolution, we see the girl was getting the soda for the boy.