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I read a sci f- short story in the 80s that I'd like to find. It's not "Unwelcome Tenant" by Roger Dee, although it has many similarities. Here's what I remember:
- It could have been written anytime before 1988. I would guess 50s or 60s as most likely.
- The protagonist somehow discovers invisible bean-shaped creatures on everyone's head.
- He somehow removes his own, and discovers everyone is repulsed by him, and he feels repulsion to everyone else.
- He works on freeing other people from their parasites, but few agree, and they are equally repulsive to those with parasites.
- Eventually figures out he's now being influenced by a different being, perhaps called "Grrr".
- Grrr seems more like some kind of octopus somewhere in the universe, with 'psychic tentacles' or something that reach across the stars to his head. (Yeah, it's a bit weird)
- He discovers if he somehow 'crushes' one of the invisible bean-like parasites, it acts like a helmet, preventing either Grrr or the beans from attaching to his head and influencing him.
- With the helmet, there's less repulsion between him and other people with parasites.
- Not sure how it ends. Could be some kind of journey (real or imagined) across the universe to confront and destroy Grrr, who turns out to be a small jellyfish-looking thing in a puddle on a distant planet.
This was probably in some sort of sci-fi short story collection, but apparently none of the ones still remaining in my possession after all this time.