Alright since i have boring old "512 joint textures" :v , Im gonna lets you sign any joint you like !
So i suppose do it :3 Well you can put anything you like ! i would start with a plain old BLACK !!!! BACKground for the joint and make sure it is Right ! Not like upside down..Well i suppose go ahead?

Go ahead ! But i recommend doing one of them , so other people could do too?it would be fair wouldent it?

gimmi them peckers. Pecs._.

You make them ! Design how you want it to be ! My pecs are just plain black . !!!!!

Do what you like

Can I sign on someone else's joint?

Well i dont think there will be space, but i recommend you do my butt
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go ahead :3

right knee is mine