This book teaches boys that 5 year old boys shouldn't cry. That 5 year old boys are "older" than 5 year old girls. That 5 year olds can fall "insta-love" to each other. Also there's girl hate. That shitty kind of "I'm in love with him so you can't be" girl hate going on.
I'm finished with book one though. This is an omnibus so there's a book two. I wish it wasn't as I'm already done with this shitty shounen garbage man book.