The Archered Wall of Harmony

Hattie asked me why I laughed. I said it was because of something on Facebook that is too hard to explain and won't be funny to her. She asked me to explain it anyway so I did.
She said "That's not funny. You know what is?
Butt remover."

When a big rubber ball rolled toward some people on exercise machines:

"Oh no, double trouble!
The ball will hit the people and they'll go flying!

…and then they won't get enough exercise."

Also she wants to write a story called "Palony princess and the Archered Wall of Harmony" which she says would be "inspired by Romeo and Juliet, but not a tragedy"
[note: I think this title is a mangling of something she heard in some cartoon, but I like it]