The Deviant ID is a picture you have as sort of your avatar (but way bigger). It shows up on your main page when you select it. Lots of people use an image of themselves (or a doll of themselves) with a solid background and they list stuff they like, their hobbies, etc., in the image itself.

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B's Bishie Strippery: You fan 'em, we service 'em!

okay but i tired to do it and it said i didn't have anything to use image wise.

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It requires more courage to suffer than to die...

You have to upload a deviation into the deviantid section.

deviantART Related > deviantID

Then you'll see it as an option when you go to edit it ^_^

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Never give up on love.