What is this?? An urchin??

[TheClown]

Honestly I have no idea. Will it harm me? What is it? Any info would be appreciated
This guy is in a tropical 10gal mostly macro tank with the stocking being
-pepermint shrimp
-an emerald crab
-4 blue leg hermits
-cerith and astera snails
-mistique zoas
-bunch of macros
-some random asternia star fish
-some random brittle stars

 

[Reefing_addiction]

Pic under whites?

@ISpeakForTheSeas