Hey! I left this comment in the main thread under your game, but you never replied, so I will try to comment hear, hoping you'll see it.
Here's an idea... You have cars at the ground level of the game but they serve no purpose. There is one that appears to have a sunroof. How about you remove it (cabriolet style), and make her have car sex? She could ride the gearbox, exhaust pipe, or "dry-hump" the top of the seat. If you like the idea, you could expand it to a small gas station (or just a single pump, where she'd masturbate using a gasoline pump's nozzle or 2 for DP. Another character might get involved, the gas station operator, who would use the pumps on her.