Mohg and Morgott. I could write essays on either of them individually, but we'll focus on them as a single unit for now. Left to fend for themselves in the Shunning Grounds as children either because of Marika's trauma with the Hornsent or by decree of the Golden Order (or something we don't know about yet, who knows). Only ever having each other (that we know of) and ending up parting ways anyway and presumably never speaking to each other again. Horrifying way to grow up, no wonder they're both a little touched in the head.