I'll smoke with anybody. I smoke out total strangers on an infrequent basis, but as a general rule. It's just part of being a gentleman, to me at least.
However, nobody shows up at my house unannounced. I don't allow it. I won't let them inside if they do.
I've never really had a problem with dick-teases either. Maybe nobody knows how to embrace their inner pervert anymore, but if they are alone and flirty, and that bothers you, well that's your own damn fault. You're hopeless.
If they are flirty and clearly with someone I just treat them like a dude.
What's the problem? Strap on your molestin' boots guys, it's time to quit making excuses.