Anime

Call me a bit old fashioned, but Lupin III. Regardless of which part or movie, I tend to enjoy some of the sometimes wacky antics that occur.

The new Bartender anime was pretty good.

In no particular order these come to mind. Most of these are outside what I typically watch, but I did enjoy them.

Monster (Crime Drama) https://anilist.co/anime/19/Monster/

Mushishi (Psychological Slice of Life) https://anilist.co/anime/457/Mushishi/

One Punch Man (Comedy Action) https://anilist.co/anime/21087/One-Punch-Man/

TRIGUN (Action Adventure) https://anilist.co/anime/6/TRIGUN/

Hellsing (Vampire Action) https://anilist.co/anime/270/HELLSING/

Overlord (Evil Fantasy) https://anilist.co/anime/20832/Overlord/

I think a lot of the other answers here are being too generous with your rules and not giving you characters that both look older and are older.

A recent one I don’t see mentioned often: The Great Pretender

It's not an anime, per se, but the writing, voice acting and such are very much like an anime in the Like a Dragon series of games. Where it currently sits, all the characters are middle-aged or older. It also has a lot of existential dialogue and side stories that are extremely poignant, as someone who is also middle-aged in this time period.

The only actual anime I could even think of with main characters my age or older that I also enjoy is Cowboy Bebop; and that's about 50-50 because of Faye and Edward. I've seen some episodes of Bartender but I wouldn't go so far as to say I enjoy it yet. It's a bit dry.

The recent film Blue Giant is great. About a young man who moves to Tokyo from rural Japan to pursue his love of jazz. Great visuals and music.

Big O

Ninja Scroll

Read or Die

Samurai Champloo

Berserk (OG)

Blue Gender

Welcome to NHK, really walks you through the life of a university dropout failed adult.

A few off the top of my head: Shirobako. Space Dandy. Samurai Champloo. Ghost in the Shell: SAC.

I loved Wotakoi. The 4 main characters are 26-28 and employed. It's in the especially rare category of adult romcoms. It's a shame the anime never got a second season, but the manga is finished so if you give it a watch and want to find out what happened after, give it a read!

Mushishi. Very serious, well-told stories told in single episodes. Occasionally a younger character will come along, but it's mostly adults, and the cast outside of the MC rotates episode to episode.

Off the top of my head, Darker than Black. Same director, different take on bleakness: Wolf's Rain. The main characters don't really have 'ages' given, but they're pretty clearly adults.

Record of the Lodoss War (a D&D campaign turned into anime, if I recall rightly)

That time I reincarnated as a slime (technically the main character is ~34, and very few children are shown, but the cast has a lot of 'childishness' in them... the style is the equivalent of a popcorn superhero movie I'd say)

Legend of the galactic heroes

Witch Hunter Robin

Van Helsing (if you just want to laugh at idiocy, simply watch the abridged series, but the actual show is good)

Dragon Ball Z, except for a few episodes every now and then. The show itself is obviously aimed at the younger shonen crowd though, if you haven't seen it.

.hack//sign (dot hack sign) is a pretty interesting one. It has several other series in its 'canon' if you like it. I'd say it was the adult oriented, well-presented premise of sword art online before sword art online was wet-dreamed up. A friend described it as 'waving its dick around because they had an actual orchestra for the soundtrack' in several scenes.

Lots of good stuff in this thread already, will suggest Black Magic M-66 and Megalobox.

I'd tentatively add Berserk to the list. Tentatively because the story does go back to recount the characters' youths, but that's really not the main focus.

Another good one with mostly adult cast and a more mature plot is Monster.

This was harder to answer than I thought, pushing up to 20 eliminates a lot of contenders I think. I would say maybe Vinland Saga? The main character starts as a child, but it also covers a large time span so he hits twenty partway through the second season. Major recurring characters are almost all adults throughout. Its a semi-historical anime set mostly in England and Denmark during a war between the two. It's a show that deals heavily with violence and trauma, has some very complex characters, and I can't recommend it strongly enough

Fullmetal Alchemist (both of them). The two main characters are basically the only teenagers, and only one of them looks it.

Heh, does western anime count?

Legend of Korra, Vox Machina, DOTA: Dragons Blood

And Pantheon.

For heaven's sake, if you have not watched Pantheon, correct that immediately.

Do 1000+ year old characters that look young count?

I mean, I don't remember watching an anime that has a character like that, but IDK some people are really weird about that.

I've completed quite a few:

• Violet Evergarden
• Vinland Saga
• Odd Taxi
• Cherry Magic!
• One Punch Man
• Spy x Family
• Saga of Tanya the Evil
• Delicious in Dungeon

Honorable mentions - depends on how strictly you'd define "mostly":

• Cautious Hero
• Frieren
• The Apothecary Diaries

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

Series

• Ghost in the Shell: Stand Alone Complex
• Black Lagoon
• Odd Taxi
• 86
• Moriarty the Patriot
• Cells at Work: Code Black
• Cowboy Bebop
• Trigun (1998)
• Psycho Pass
• Aggretsuko
• Panty & Stocking
• One Punch Man

Movies

• Patlabor
• Patlabor 2
• Ghost in the Shell (1995)
• Ghost in the Shell 2: Innocence
• Redline
• Porco Rosso
• Howl's Moving Castle
• Paprika
• Dead Leaves

Eureka Seven

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