Douman Seiman (aka Dowman Sayman) is my favorite manga author of all time. On a surface level, I connect with his artwork a lot. I've always been a fan of unconventional looking manga, and his super 2d and sleek characters coupled with the godly linework that he's acquired over the years gets me fucking hard.
The real meat, though, is his ability to come up with the most bizarre and interesting stories. His work catalogue's mostly oneshots and short stories (barring some longer works, like Voynich Hotel). Nickelodeon and Melancholia are great examples of this, both being a collection of short stories loosely connected to each other. The stories he writes have a pretty wide variety of different topics/themes (you can really tell that this guy's into a lot of things, a good number of those things being obscure shit because if you haven't guessed already he's a weird dude).
What is consistent are the batshit insane/wacky characters that tend to kind of accept the absurd things that happen in their stories. It's this kind of dream logic that's universally accepted as normal.
If you're an ADHD fuck like me who has an insufferably short attention span, give Douman Seiman a go. His stories are nice short bursts of dopamine, quick enough to move on to the next, but memorable and satisfying enough to be a worthwhile investment.