Gegege no Kitarou
Where's the BL I was promised Ch 33 Ok joking aside this is kinda fun to read. The author gives no fucks about continuity though. The first 15 chapters are more linear with the storytelling, and then the author throws away any plotline from those chapters and makes it episodic (Black Jack-esque but without the doctor husbando). Rat-man is immediately retconned to being Kitaro's friend, that one guy who raised Kitaro is stuck in off-screen purgatory, and Kitaro is now the strongest yokai in the world. It's pretty great. Not exactly something that you'd want to immediately finish in one sitting, but definitely high quality entertainment for a really old children's manga.
Tsurezure Children
I remember watching the anime as a kid and not being able to tell any character apart.
KAIJIN FUGEKI: Kindled Spirits