What if, for the aliens to water their humans, they not only have it injected through their suit while they sleep, but they have something like a hamster water thing, where humans can drink out of a little spout in the side of their enclosure? Like a water fountain you'd find in a school, but if the owner really wants to go all out for their human, they get a small "waterfall" cause some cosmodians think that their humans would be happier to have a more natural way to drink it, like how some humans get water fountains for their pets so that the water is constantly being moved?
Just to clear something up, the only time "water" was injected through the suit is when y/n, aka Stardust, was refusing to eat and they were given an IV fluid to prevent dehydration/starvation. But it's not meant as a long-term solution, it is not good for the human body to live on it.
Otherwise I can see homes back on Daykaair having such options for their human pets to drink from, just like we do. I have a little water fountian bowl for my dogs with a filter.
But the real question, do they drink liquid water in space?
I had come across a couple of takes on this, from water fruit to having devices that takes the water out of the air and body.
I might go on a similar route as the slime with thick water, something we have here on earth. But haven't really decided one way or another.