Red and Gold (смешанная)

Sasuke knew as much as anyone about soul marks. Every injury his soulmate got would reflect on his skin in color, which was normal. A little slash of color here or there as his soulmate got nicked by a kunai or stumbled while making dinner was to be expected. If they healed up without scarring, then the mark would be gone like it had never been there in the first place. There wasn't even any pain.
Soul marks that reflected endless, permanently scarred bite marks from the age of six onward were emphatically not a good sign regarding his soulmate's situation in life.
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PLEASE READ THE TRIGGER WARNINGS FIRST. This story deals with some very unsavory subjects due to the nature of the soulmate-identifying marks and the characters involved, as a result of the backstory that canon provides for Karin, and the assumptions and theories that people make based on her scars and the locations of such.