User blog comment:Aphrodite Sweetheart/Official Winx Club WOW and 4th movie discussion blog/@comment-31707409-20170424000453/@comment-29197449-20170424023306

I mean, you can tell by watching the series.

Jim never allied himself with the Winx; he was simply working with Bloom to stop Tinker Bell. From how Tinker Bell and the Shaman talk about Jim in Episode 8 or 9, Tinker Bell didn't seem fond of Jim, so it sounds like he's actively working against her. The Winx took down Tinker Bell in the last episode and, with her gone and the reveal at the end of the season, it seems like Jim needed Tinker Bell gone to kickstart some plan he already had in motion.

He's kind of like the bigger bad behind Tinker Bell's big bad, if that makes sense.