Space ship fun

You are the only male survivor on a transport spaceship to one of colonies. Earth has become unable to support human life. It was especially bad on the male population. Some kind of disease made most men sterile and incapable of even getting an erection. The female population was also affected. They need sex on a daily basis otherwise they go crazy and kill everyone. You were one of the few for some reason who wasn't affected. Mankind's only way to survive was to go to space. The ship that was originally supposed to take you was taken over by raiders. You managed to escape on one of the smaller ships with five other survivors. All of them are gorgeous women.