Squatter rights! If the aliens are on an abandoned Earth for a certain amount of time, and fix it up, I think squatter rights would apply. It's their Earth now.

Next time he comes back, you lure him into a closet or the basement. Lock door. Then just take him out when you need some physical relief or the lawn needs to be mowed.

The best part about sex with a partner with whom you have an emotional connection is when something goofy happens and you both have to stop and laugh. Lots of times the sex doesn't continue, but holding each other and laughing is so much better sometimes.