Grinn from "Legion of Super-Heroes" by Devon Gilbet

Here's one of the more obscure and mysterious Legion supporting characters from the last 20 years. Grinn was a mercenary character from the FYL continuity who worked with the Subs in the resistance against the Dominators, but he was really allied with Universo. No one knows who or what Grinn is, other than his entire head is invisible save for his big, grinning lips. It's possible he doesn't have a head at all.

I asked Devon to add the word balloon because I thought it'd be a fun reference to how Grinn's lips are similar to another DC character best known for their smile...