Pain. Pain’s Akatsuki ring is blue or yellow with the Japanese Kanji 零 (“Rei”), which means “zero”.
That’s a really good question ^^; So basically, the rings are just to identify Akatsuki members. It’s not like they have any special powers or anything, they’re just basically like a gang ring and they use them as a way to know who’s in the group and who isn’t.
12 reviews for Akatsuki Rings Pain’s MEANING 零 (lit. “Rei”) Anime Cosplay Metal Finger Adult Ninja Props Accessories Cool Stuff Gift