Wisp

The Wisp is an enemy which is similar to the Blue Bubble; it will jinx Link if it touches him, however it is non-agressive and will simply float around. You can't hurt them with your sword but you will be able to draw them in with your Gust Jar.

Quote from The Legend of Zelda: The Minish Cap Wisp figurine: "Appear in dungeons. They float in midair. They won't hurt you if you touch them, you won't be able to use your sword for a while."