Looks a lot like a silverfish. It's a bit fatter than the ones I see here. I have given up on eradicating all bugs in my house. It can't be done, anyway. I try to allow a balance - little house spiders hiding in crevices are good for keeping small-medium bugs at bay. Allowing mud dauber nests on my brick facade here and there keep larger spiders at bay. Silverfish, if you don't see excessive numbers, are harmless. I get rid of them individually here, but if you have a lot of them, set off a bug bomb in your attic. They enter walls from above. Spreading diatomaceous earth in the attic or using sticky pad traps will work, too.
The truth is that human habitations are great environments for bugs. If you allow a reasonable balance, rather than just trying to kill EVERYTHING, you will have a lot fewer bug problems. All that constant chemical assaults accomplish is creating generations of pesticide resistant bugs. The ones that survive the assaults procreate and make the successive generations harder to kill. I allow lizards, spiders, and mud daubers to live on my property because they keep other populations in check and they rarely show themselves.
It's cheaper than repeated exterminator visits, too. Bugs are a fact of life here, no matter what you do.