This trick is very much a novelty trick that starts like a Cutaway and ends with a Back Catch, with the flyer caught from behind by the catcher. A return to the bar is very difficult if not impossible.
Swing out, turn around and get into a Cutaway position at the platform. At the frontend, let go and hold the folded position by grabbing your legs. The catcher grabs you around the butt from behind.
Thanks to Ella Shea (flyer), Lukas Weinback (catcher), Kevin Vu (lines) and Sarah Brownstein (on board)