We Are Really Childhood Sweethearts

If You Have Trouble Finding a Book, Please Recommend It to Me.

I was looking for a book where the male protagonist and female protagonist were named. I forgot what they were. I only remember a few scenes in which the male protagonist had to put meat in the rice and then pick it out for him. There was another one where the male protagonist and the female protagonist's brother invented something. Once it was put in, the female protagonist went to the male protagonist for help.