Never underestimate the power of a raging libido. Humans like to think up all sorts of higher reasons for why we do the things we do, but at the ba<x>se of it all is always finding a mate. Observe the endless and exhaustive courtship behaviours exhibited in the animal kingdom, and you realise Freud was onto something.
Friendship charity curiosity. Its entirely possible that the only desire here is the desire to travel. But then theres always that small chance its not.