Friend or Foe?

[4n2xtacy]

Hi guys, please I need help with this. Got back from vacay and saw this on the rock. It's hidden and out of the way of corals but the fear of the unknown is what worries me. Is this a Friend or a Foe?

 

[Crabs McJones]

Does it move? My initial thought is a sponge of some type. If so harmless :)

 

[ReefQueen]

Very hard to see in the pics, but it looks like it may be a sponge. If so you can leave it.

 

[DangerDave]

+1 on a sponge, better pics may help confirm...

 

[4n2xtacy]

Thanks guys, unfortunately, this were the best pics I could get as it's so hidden I had to zoom in on it. It doesn't move. I did suspect it to be a sponge but on a closer look, it looked like it had tiny tentacles but on the other hand the tentacles never retract even when touched. So maybe it's just an uneven surface.