Well, it depends on the ghost, anonymous, as each ghost is its own species with its own requirements. I’m a little concerned about the sweetness of this drifloon, however, as drifloon are rather notorious for acting sweet until you grab hold of their strings, at which point they try to carry you away to parts unknown. Of course, the likelihood of it succeeding is slim (as drifloon can’t even lift a toddler on their own), but still, be wary of possible ulterior motives when it comes to wild ghosts.
If the drifloon actually wants to live with you for reasons that have nothing to do with your soul, then I do admit that ghosts are generally easier to take care of than most other pokémon. Mostly incorporeal ghosts such as the gastly and drifloon line are clean in that they don’t need baths, nor do they relieve themselves, thus eliminating two of the less desirable aspects of raising pokémon. They still may make a bit of a mess (as they’re far more mischievous in general than most other types), but this would be limited to typical poltergeist activity. This kind of behavior is difficult to train out of a ghost-type until you bond with it to the point where it takes your requests (for it to stop tossing your possessions about) seriously. Try to occupy it with soft toys instead—anything you wouldn’t mind allowing it to throw about.
By and large, while most ghosts are nocturnal, this is not the case for drifloon, whose normal hunting habits require it to be awake during the day, when its typical prey (small children) are awake. Thus, don’t be surprised if your drifloon keeps the same sleep schedule you do. Additionally, when they sleep, most ghosts prefer to take on incorporeal/invisible forms, to float in an unreachable corner, or to simply rest on a shelf where they can’t be bothered, depending on the pokémon and their usual mode of self-defense. The drifloon family prefers the second method, which means the usual beds I would recommend are not necessary in its case. However, be sure that your drifloon rests in a room without a ceiling fan or uncovered vent, as your drifloon won’t be consciously monitoring where it floats as it sleeps.
Normally, a drifloon’s diet consists of … well, let’s just say there is absolutely no way you can procure what a drifloon normally eats without being arrested. Luckily, drifloon will happily take most human food and poké-kibble as a replacement. As a general rule, ghosts (with the exception of sableye) are omnivores, but most, drifloon included, lean more towards a carnivorous lifestyle than a herbivorous. However, while scientists have argued for decades over the subject of what, exactly, the more incorporeal ghost-types get out of eating (as they don’t seem to need any particular set of nutrients), it’s always worth it to feed them a variety of foods, rather than feeding them exclusively meat. Granted, you could also get away with not feeding them at all, but this may encourage drifloon to go out and hunt your neighbor’s children instead.
As for activities, your drifloon won’t actually need much exercise, and ghosts by-and-large already have a full mastery of their powers by the time they make themselves known to humans. When the two of you get closer, your drifloon may allow you to hold one of its strings, at which point, it’s fine to take it outside and get it some air. Try to avoid taking it outside before it allows you to hold onto it, however. A stiff breeze may separate the two of you, and that would be rather unfortunate.
If you happen to be a trainer, however, it’s worth it to note that most ghosts can learn a variety of moves, and they tend to be eager students. Drifloon is no exception to this. What I mean to say is that it’s worthwhile for trainers to capture ghost-types, as these are quite easy to train (once you get past their mischievous streaks) and quite capable of being rather flexible on the battlefield.
But most importantly, anonymous, keep your drifloon away from small children. Technically, the child won’t be in danger because, again, drifloon can’t carry off a toddler on its own, but it will be just the worst for drifloon’s self-confidence.
Good luck, anonymous!