What kind of Crab?

[Purple Penguins]

I found this cute little guy in my button polyps, well not really "IN" them Under them, He made a gave under the flesh of my colony causing stress on them, I knew he was in my tank over a month ago when I found his molt but I have not been able to find him till last night, Im thinking some kind of decorator crab but not sure, and due to him messing with the Polyps the way he did even tho I think he is cute his new home is in my refuge.. Please help with the Identity of the crab I named "Eek"

 

[fanaglethebagle]

I think it is a type of crab that commonly makes burrows in soft coral. Sometimes it can cause infection, but some people think they protect from predators.