Drifloon shares some similiarities with other Pokemon. Though the similarities are mostly minor, they are interesting.
Absol is a signpost for impending disasters. When you see one, a disaster will occur soon after. Drifloon is similar in that it is a signpost for wandering spirits. Both Pokemon warn of something malevolent occurring around them. There is very little else connecting these two Pokemon, but they are both sufficiently creepy.
The evolution line of Igglypuff, Jigglypuff, and Wigglypuff are the original Balloon Pokemon. They share physical similarities with Drifloon: their swirly hair and balloon shape. Like Drifloon, these Pokemon look innocuous, and use their looks to attract people and Pokemon. They then use their voices to sing, putting targets to sleep.
Qwilfish is the only other Pokemon called the Balloon Pokemon. It resides in the water rather than the air, but like Drifloon, it finds moving itself rather difficult. Like Drifloon floats through the air and goes where the wind takes it, I imagine Qwilfish floats through the water going where the current takes it.
Aipom shares some physical similarities with Drifloon, most notably its colors. Its tail, oddly enough, look like a glove balloon, even. Aipom's evolution, Ambipom, is purple, yellow, and a reddish tint. Drifloon's evolution, Drifblim, adds red into the mix as well, with its red eyes.
Litwick is another interesting Ghost-type Pokemon. It looks like an inviting candle that will serve as a guide, and it drains the life force from people and Pokemon who mistake it as benevolent. The life force it steals is what makes its flame burn bright. Drifloon has a similar duplicity, looking like a fun, inviting balloon, tempting children to grab hold of it so it can drag them to Hell.
Another Pokemon that could possibly look inviting to children but is sinister like Drifloon is the Ghost-type Pokemon, Banette. It is a discarded children's toy that turned into a Pokemon out of feelings of hatred after being thrown away. This creepy doll is on the search for its original owner. I don't want to think about what will happen if they reunite.