Sexual liberation and freedom.
Although the character's experience of reality is typically limited, the reader sees the whole network of sexual relationships. The truth is that, although Carlotta is very sexually active, so is her mother—her mother sleeps with her husband after all. Carlotta ends up being the mistress of Suwelo in a plot reveal, and Suwelo's wife ends up getting groovy with Mary Jane, who freed the girls from prison in South America.
The "Anima" complex.
This novel seems to be thematically informed by the idea that Suwelo is having an encounter with parts of himself that he doesn't understand. When he goes to different women to find romance with them, he is looking for himself. "Lissie" is the personality he associates with that process, but when he accepts the situation for what it is, and when he finds that the correct way to integrate Lissie is actually to commit to his wife, then his marriage is restored. Although Fanny is the one who goes to therapy, Suwelo's story is its own therapy.
Commitment and trust.
Although the novel seems to suggest that wayward sexual behavior is just part of what it means to be human, that doesn't mean there isn't also a thematic reason to be committed to someone. We see from Suwelo's story with Fanny his ex-wife that actually, there are very good reasons to commit to a specific partner for life. For one thing, it makes life far less hectic and painful, but it also provides a kind of sanity and stability to life, having a friend and partner to depend on—but that must be a relationship built by trust.
