I’m a big fan of Godzilla and Gamera. I mean, I spent my Saturday afternoons watching Creature Double Feature on channel 56. Then in the 80’s, they added Kung Fu Theater after it. Shoot, i think I didn’t go outside on a Saturday from 1976 until 1991!
In the Gamera remake, there’s Sports Team Walkman guy in the first Gamera movies. Basically a colorful guy (literally). He is animated about the music he listens to, talks to his girlfriend in an animated way. They’re all wearing stick on tattoos in the colors of their favorite sports teams. Well, Gyaoss (the sonic pteranodon) eats them.
Except the character was so well done, the character was brought back for the second Gamera movie, and you could tell from the way they played it up he’d been a smash hit in the first movie, and audiences must have laughed when they saw him. He appeared in the third movie in a cameo scene as well. Nobody was really bothered by the inconsistency of their being eaten by a batlike monster yet reappeared (alas, the helicopter pilot from the first Gamera movie with teeth like Gamera’s never reappeared).
We have no idea why he was a big hit with audiences.
Some of your characters will tend to steal the show. There’s entire chapters in writing books on how to deal with them. What it boils down to is, if they’re stealing the show, either give them a one scene appearance or make them an essential character.
If someone really steals the show, then bring them back for a cameo in another book. There’s something about them the reader responds to.
The flaw to these characters is they’re usually not colorful enough to sustain an entire plot by themselves, but they’re colorful enough to interrupt a novel or movie in a small richter scale story earthquake.
Either cut them back, bring them back, or see if the character can sustain prolonged exposure without damage.