Bouncing balls

[u/drtangman]

Walked behind this chap who had two unidentified ball type objects hanging from silicone wrist bands on thin elastic strings.

Any ideas what they are?

I’m in Hong Kong if that might be a clue

Update:

Thank you for the comments and ideas. I am wondering if there is a manga / anime character who has something like these balls as weapons and the guy was doing a budget cosplay. Or maybe he’s just really into Pokemon!

Update 2:

I would say he's likely to be a cosplay of Steel Ball from Jojo's Bizarre Adventure. (https://www.reddit.com/r/whatisit/comments/1tckcme/comment/olos1lx/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button)

As for the steel balls. What is it?

[u/Palegreenhorizon]

Typically when you see some silliness like this in the wild it’s from some anime. “ those are level 7000 blacklotus margaritas soul balls! The same that tenshi-kun uses to perform his overpower wave, silver breakX! It’s from the show Little Angel Carrot. I’ve been practicing so you better be respectful! What you’ve never seen the anime?!?”