Well.
This is thoroughly ridiculous, but I'll go into it.
The only relationships I can see as being possible is in business, or with insane characters on either or both sides of the relationship. As it is, I don't think many get along with them because they're kind of creepy and probably have bad reputations. Gaudi are, from what I can glean, either dumb or smart enough to fuse two weapons and make a really cool one on the spot with only a counter with maybe a couple tools on it. So, with different races also may come different relationships. They might have an intellectual kind of partnership with someone outside their race. Or they could be their pet. Thinking about much else makes my stomach churn, frankly xD