I think this is a nice, simple idea that would have been done already but here goes:
A 3D Black Belt Model that circles around the Tori.

I made a simple sketch to show the ideal location of the belt - just underneath the lumbar joint but wraps tight to the rectangular stomach of the tori. The inspiration for this model comes from a standard BJJ black belt made from a black canvas material with a red "tape" on one end. Below I linked my sketch and other pictures for reference.




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If you guys want you can go crazy and make colored copies of this item for each belt rank.