I'm curious what kind of stuff there is that has a similar form of sexual interactions as LonaRPG. Not specifically in the sense of the top down perspective but the generally free form and potentially usable in combat kinda stuff.
I don't know about real-time games but there are a bunch of games with turn-based sex systems. This thread lists most of them, but excludes some games that have sex integrated in the combat system, e.g. TH Claire. Anyway, the big one I recommend is Karryn's Prison, though unlike Lona, it's turn-based and nominally consensual.