Sure. If they agreed. They certainly wouldn't enjoy fucking someone I couldn't stand. No more than I would enjoy fucking someone they couldn't stand. I just hope they'd be able to steal themselves through the ordeal for world peace. I'd certainly pamper the shit out of them afterwards for doing something they loathed so much and being so selfless.
And then have sex with them to help erase the event and re-connect with the person they love most having sex with. Me.
Seriously. I'd feel badly for them. If someone asked me to have sex with someone my partner loathed for good reason my skin would crawl off but would take one for the planet. I wouldn't enjoy it, but it no worse than Cleaning up dog shit or someone's puke off the floor. If I'd do that for world peace, I'd suffer through 15 minutes of getting some obnoxious twat off.