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of course it is fine. It all depends on what your story is. Remember, the antagonist doesn't have to be the bad guy... just has to be someone the protagonist has a conflict with.
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#3: Attribution notice added
Source: https://writers.stackexchange.com/a/43433 License name: CC BY-SA 3.0 License URL: https://creativecommons.org/licenses/by-sa/3.0/