Exclusively zoo? Not quite. But it's a preference. Wife and I have sexualized relationships with friends, family, pets. Not a requirement, just a possibility in any relationship we have. That said, while she is comfortable, relaxed and open to animals and humans alike, I tend to prefer, fantasize about and look forward to sex with animals. I am so selective about human partners that... just really don't think about them much. Most women? Love them to death for conversation, joking, etc. Not really that curious about, interested in or driven to see human vulvas as I am dog or mare vulvas. And men and their cocks? What I like about mine I like about theirs.