There is a lot of experimenting with gender identities in this book, but all the gender labels seem to be assigned by Raoule.
She is the one who describes Silvert as “a man as weak as a girl” (41) and thereby first assigns a female identity to him. She flips her identity between that of a “gentleman” (55) to “a woman right through to her pleasure” (56) then back to “ drowning man” (58) in a short time span. She usually applies the identity of a man to herself when it has to do with her relationship with Silvert. She says that “this man is in love” (68) or that she’s “a man madly in love” and then again “a man in love with a man, not with a woman” (73), where she also assigns the identity of man to Silvert. Yet she later declares that he really is a woman. She calls him a “beauty”, says he has an “instinctively feminine soul” (74) and decides to use female pronouns for him.
Raittolbe seems to understand her because he tells her before she claims a manly identity in front of him that “two boys hearts, two hussars’ hearts must both be much the same color red” (54). I think that is what makes her accept his advances and afterwards trust him enough to confide in him about Silvert.
There is one instance where it is mentioned that Raoule’s aunt calls her her nephew when she paints or fences (28). However, Raoule uses that too when she tells Silvert “remember, now, that I’m a boy. An artist whom my aunt calls her nephew” (37).
So we see here that Raoule finds power in language and naming, a power that women usually don’t have, but that she is able to exert because of her wealth and social status.