It's got some good gags in it. It's very weird and largely unpredictable, though some of its recurring storylines do follow set patterns. Common points of humor include public nudity, taboo sexuality, murder and gore, and sacrilege. It references various aspects of pop culture such as movies, manga, and paintings. Some of the artwork sucks, but I decided to rate it more highly because I appreciated the variety and novelty of a lot of the art.
The manga starts with a plotline about the happenings in front of a door peephole, with murder and salesmen being involved. The recurring storylines of the manga cultimate with many if not all of them ending up in front of that same door peephole (though after that conclusion, there are still a few standalone gags and an extended piece). The main recurring storylines are as follows: Takashi and his religious awakening, the classroom of infectious twitching, the cute serial killer Kuma and the detective on the case, the spirit rejecting and defacing the manga, the various garbage days, pictures which look like two things depending how you look at them, the over-thinker on the train, and the wistful gazes into the nightsky near the creaking factory. There are also several other scenes or details which show up maybe twice or so, but for the most part, the rest of the stories are standalone.