Komachi is about the lazy. Her job is important (she is basically the Charon of Touhou, ferries the souls of the dead across the Sanzu), but she nonetheless tries to slack off as much as possible. My favorite Touhou girl is also a lazy redhead, so here they are both doing the sleep on job.
The cannons, they are of large caliber. That scythe is a rather tame one, some artists take pretty wild liberties with it and make it into all sorts of weird and unpractical shapes. Not that the scythe is all that practical a weapon to begin with.