TikToker Dakota Harper says it's all his ex's fault he's been busted for arson ... essentially calling her a bad influence.

The social media star -- who's been accused alongside former girlfriend Felicity Eatmon of setting an abandoned home on fire -- told Los Angeles Magazine that he wouldn't be behind bars if he'd just stayed away from her.

In a phone call from a West Virginia Jail, Harper told the outlet ... "I need to stay away from Felicity. She’s the reason I’ve been in jail ... if I stayed away from her, I would not be in any trouble."

He's been in a bit of trouble with the law over the years -- L.A. Mag says he was named in a 2023 truancy complaint for skipping school and was charged in a pending case with misdemeanor unlawful removal, injury to or destruction of property, as well as conspiracy to inflict injury to a person or property this past May.

And, as you know, he and Felicity were arrested late last month for allegedly setting a vacant home on fire in Charleston, WV.

A judge recently doubled Dakota's bond ... upping it from $10K to $20K.