That does not sound right to me.
I have had my bd at times "Need a bath" after getting some poop on him and a nice bath made him clean and odor free.
you might want to check the area and see if some kind of old food or other stuff is hidden from view and perhaps you just notice it at that time?
also sheding skin should be clean and *DRY* if your bd is having any area where the skin seems to be moist / wet and he has not been in the water then check that out asap.
if that shed is moist then it *MAY* have an infection that needs to be treated.
depending ....
1) is it a normal shed (with the rest of the body)?
2) could it be an injury trying to heal?
3) if its one area and moist it could be a blister on an area that has been burned by heat or by chemicals like an acid or cleaning solution like bleach / lye etc....
I hope it's not some bad problem....
the above is just some ideas to check out and rule out (I Hope)
depending on how the dragon is housed and such He may have got into some trouble when you were not looking...
they can and will seek heat and light, and do not understand the effect of contact with a hot light bulb for example.
that beeing one way to get a burn in a cage.
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