Six line discoloration

So I noticed some discoloration on my six line this morning, just got home and its still there. Its right behind its eyes on one side of its body. Here's a picture, any ideas? Rubbing on a rock maybe?

 

Hard to say, might have got stung by a coral.

 

Do you have a serpent brittle star?

 

Maybe it got stressed from something. Give it some time and see what happens...

 

Yes ma'am I believe so, small always stays inside my purple star polyp rock. Atleast when I see it that's where its at.

 

Sorry I should have been more specifc.

I am thinking of the large green serpents and banded brittles.

 

I have added a porcelain crab lately, idk if its the culprit

 

Naww, but porcelains are too cool.

Sometimes when wrasses sleep they can fall victim to large serpent stars or preditory crabs.

Hopefully he will just keep eating and it was a wound from the LR or something similar and will disappear.