Yep, if we're going Sci-Fi there could be plenty of places with them.
Could be a Tropical world full of people with Hot Beach Bodies.
There could be a Snowy Planet where all the women are thick and have some extra chub on them to stay warm.
There could be a Jungle World with muscular Amazonians.
This is definitely a more helpful and symbiotic relationship between Humans and the Sexymilators instead of having them be Invasive.
It is actually an interesting way to have humans in a space setting without getting their shit wrecked by other aliens, the symbiosis of humans having intelligence and ingenuity while the Sexymilators have the biological advantage, together they're much stronger.