It's basically a flying fuselage and could be described as a rectangle.
The sides/ends/wingtips are angled as they would be on any basic trainer wingtips. if you can understand what I mean.
He is a reasonably experiencied RC flier, also he is an avid experimenter and does work outside the square a lot. (generally with success and the odd failure, I might add )
I've told him that he's really done it this time, but he's convinced I'm wrong!