>>528236601
Didn't The Pale Princess and the 6 Pygmies books already imply he and the other sinners stole the power of one of the Light Prince? I think Skirk's SQ only strengthened this theory with how she said any strong power is absorbed by others, it never actually disappears. Just for reference, the Pygmies are the sinners + Dain.
https://gi.yatta.moe/en/archive/book/21/the-pale-princess-and-the-six-pygmies?volume=6