I believe that any tickling involving my balls would have to be considered sexual in nature. 😛
Seriously, tickling can be a very sexual thing for me, as I seem to have a fetish, paraphilia, or whatever one chooses to call it, but it does not have to be. It all depends on the context, although I do tend to avoid tickling outside of a sexual context. The primary reason for this is that I, like many others here I'm sure, do in fact feel a "stirring in the loins" when involved in a playful tickle encounter with a member of the opposite sex, which has made me self-conscious about any awkwardness that might arise. (no pun intended..well, maybe not..) As to Question #2, um...yeah...