there are some nice spots in silvermoon forrest imho  (and you dont need to be level 70 to get there if your horde)
one at the waterfall which nobody ever goes to

but also there is one or two houses where almost nobody ever goes
but you may have to share the place with a npc, which is not too bad but not really nice for the roleplaying

you could just find a nice inn in a town

in all cases using party chat is recommended ;P



oh .. and you could always go into some instance if you want to make sure nobody catches a glimp of you two together without gear or whatever you wanna do :P

On that note, I once witnessed a Blood Elf girl wearing her undies perform a reverse cowgirl on an Orc male wearing only his loin at Shattrath City.  She just kept 'sitting' on him repeatedly.  He seemed expressionless mind you.  Maybe from the overwhelming ecstasy?