How to ejaculate during lucid dreaming without making a mess?

Hello!

Occasionally I lucid dream, and when I do, there's no better place to visit than the tropical amusement park that's partially been converted into a massive orgy/harem. Good times to be had there, let me tell you. I'm often on the edge of being able to control the dreams, but I don't ejaculate during the sessions. (Rarely, in fact, do I have sex.) I think that a part of me feels apprehension about creating a mess of my bedding, which is "stunting my creativity".

Waking up enough to put on a condom would stop the dream. Any ideas for other contraptions to keep things clean? I was thinking maybe something like a hairnet that could easily be slipped on. Maybe an inconstance shield?

Thanks!