Aliens try to have the human race repopulate

[Reciter5613]

A story where humanity is close to extinction and aliens try to have them repopulate in any way possible.

Basically something like this:
https://e-hentai.org/g/1261666/a3424e839a/

 

[Ben Rosewood]

It could be interesting if you expand on the idea.

For example:

-Why do aliens want humans to repopulate? Are they intergalactic trade partners in the future? Are they experimenting further on humans?
-Do the aliens have to also protect humans from some other hazard (other aliens, a disease)
-What if all men or women have been wiped out? Now the aliens have to re-create sperm/egg somehow (maybe from other species). Does that cause changes in humans (futas, increased libido?)