Trochus snail STUCK in infinite loop!

[JPG Corals]

Came home to my trochus snail stuck in this Infinite loop with another snail :grinning-face-with-smiling-eyes:.

Have you seen this before, will it ever stop?

 

[Ron Reefman]

Never seen that exact thing before. My guess is it's eating algae off the shell. I have Astrea snails, Nerite snails and Cerith snails and they all do shell cleaning on each other.