Holly happens to look up at the staff table at the same time that Quirrel has his head turned away from her and it sends a stab of pain through both our foreheads, which has me covering a non-existent scar. That... should not have happened. I sincerely doubt that my little choker somehow spread Voldemort’s soul piece into both of us, especially since I’m not a parselmouth, but I never really considered that it might extend the link between Voldemort and Holly to me. I look up at the staff table. Snape is looking right at the both of us, and his expression is... complicated. I can’t even begin to pick apart the emotions I see there, although I do think that loathing and guilt are two of them.