You know, I reviewed this thread. The underlying issue has been covered several times throughout.By sexual assault I mean if somebody touches you in a way they're not supposed to. That might sound quite broad but to put it in simple terms, if somebody touches or tries to touch you on any part of your body that's covered by the bathing suit, without your consent.
It's not as simple as "he touched me there, so I can use lethal force." It's not going to be, no matter how much you think it should be. You'll find various phrasings of this throughout this thread (and several other threads on self defense): You may use ONLY the force reasonably necessary to safely resolve the situation. Reasonable is a common-sense interpretation -- if a normal person of ordinary intelligence and sensibility would feel that it is sensible. Use too much force, and you face likely criminal and civil consequences. Don't use enough, and you won't escape. Strike the balance, and be ready to deal with the legal consequences anyway.