A YouTube web series that’s well written, acted and shot? They are rare, but here’s a fine, new example called Mythomania, which is written and directed by comic book artist Derek Kirk Kim. The story revolves around a group of aspiring cartoonists living in L.A. It’s essentially a modern boy-meets-girl story. Andy (Jeremy Arambulo) dreams of winning an Eisner, but his work has been turned down again by a comic book publisher. On the plus side he’s just met a cute comic book artist Ashley (Simone Lamar Carter), who he introduces to his cartooning pals. It’s got all the usual geek culture awkwardness including the typical macho ragging that goes…