Chet Castellaw

Jermaine Jackson has a laissez-faire attitude when it comes to his niece Paris Jackson, because he's down with her getting hitched at 17 if she's truly in love. Paris and BF Chet Castellaw were photographed Saturday coming out of a Calabasas coffee shop and she was wearing a ring on her engagement…

Paris Jackson's coffee run with her BF is stirring some buzz she might be engaged -- but a closer look has us thinking ... it's not all that serious yet. 17-year-old Paris and Chet Castellaw -- an 18-year-old soccer player for Real So Cal -- hit up a coffee shop in Calabasas on Saturday, and when…