In some jurisdictions, squirrels are illegal to own. You need to check your county code or city ordinance. Generally, animal control or the department of fish and wild life enforces the laws pertaining to the keeping of animals. I would also contact your local veterinarian. I once had a similar situation and my local veterinarian knew an organization that rescued baby squirrels. If you have a rental agreement, you need to review it to see what, if any, restrictions are imposed regarding pets.
This is not to be construed as legal advice. I do not have an attorney client relationship with you.
Sounds like your roomate's boyfriend is a little "nuts." Sorry, I couldn't resist. Legally, your lease may have something that prohibits pets or requires an additional pet deposit, etc. Obviously your landlord would prefer that you handle this internally. Otherwise, getting the landlord involved puts you on the radar so to speak. As far as local laws or ordinances prohibiting someone from owning a squirrel, you can check online for your locale for county and city ordinances. I am not aware of a SC state law that addresses this situation. My suggestions is that you and your other roommates tell the girl that everyone is uncomfortable about the squirrel and suggesting that it be turned over to an organization, such as Keepers of the Wild, to be rehabilitated and released.
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