By adult I mean over 18-20 years of age and with adult appearances. Nothing against anime with younger characters, but interested in finding some with older characters.
I’ve completed quite a few:
- Violet Evergarden
- Vinland Saga
- Odd Taxi
- Cherry Magic!
- One Punch Man
- Saga of Tanya the Evil
- Delicious in Dungeon
Honorable mentions - depends on how strictly you’d define “mostly”:
Honorable mentions - unique circumstances:
- Cells at Work! - Your typical red blood cell lives for about 120 days :( The cells that look like adults do behave like adults though
- PLUTO - Robots’ mental age can be different from their physical appearances
The only one I’d take issue with here is Spy X Family. I think it’s more of an “all ages” show that focuses heavily on Anya and her classmates antics. All the rest make sense!
Saga of Tanya the Evil
Uhh, the main character is technically a child, even though they >!have the mind and soul of a middle-aged man!<. I’m not sure I’d include this, but the other characters still work.
The rest of the cast appear to be adults though.
One child among numerous adults satisfy the definition of “mostly adult cast of characters” that OP asked for IMO.
