It is a quote from Aghora one of the last metabarons (a clan of warriors who overcame their physical frailties through insane mental discipline).
S/He was fighting a being who couldn't be defeated through physical means because it reflected back any attack directed against it by creating an exact physical copy that was connected to the agressor in every way. Essentially it was like attacking a vodoo doll of yourself.
The metabarons through extreme training believed they fought with more than just their bodies but their spirits as well. Aghora was basically saying that the creature couldn't copy his/her spirit, and because of this it was doomed.
And yes Aghora is a hemaphrodite (a male brain in a female body) - Her/his father's work: long story.
Aghora is a hemaphrodite. It's a long story. Basically her father Steelhead the supreme metabaron (supreme because he was the perfect remorsless warrior), performed surgery on his twin children as part of a compromise with his wife.
His daughter was born without a brain (he's the only one who knew) and his wife wanted him to raise a female child (the clan's code allowed only one child) because it would mean that Steelhead loved her (long story: and only a male could inherit the metabaron title).
So he basically installed his infant son's brain in his infant daughter's body.