Nubobo

About
The Nubobo is a type of monster that largely resembles a Ghost, due to it's physical appearance and incorporeal form, but this is just their data being very similar to them, which leads them to share many of their properties. Most humans just refer to them as ghosts though.

They are mostly yellow, with a few rarer exceptions, and have two huge eyes with an equally big mouth and make a very goofy expression, as if mocking their enemies all the time, but this is actually just how their face looks. They can float around and go through solid objects, much like how Ghosts do, but they can still use their hands as whips to hit their enemies in combat, which is their primal attack.

They are not quite so fearsome since they are very weak and silly, but they can still be pretty dangerous for inexperienced adventurers due to their immnunity to physical attacks, making magic the only reliable way to deal with them. However, they are still coward creatures and will run away if they are attacked to heavily even if they don't suffer any wounds. Magic is the only way to take them down for good, otherwise they would just run away every time and just serve as an annoyance to adventurers, who will get more irritated the more the Nubobo escapes with that mocking look on his face.