Loving all of the Odd Taxi mentions.

• Planetes (sofa king good)
• Hellsing
• Area 88
• Genshiken (adults but college setting)
• Read or Die
• Gundam 08th MS Team
• Excel Saga (the main cast are all adults, but it’s a comedy and just about everyone is an idiot, so they won’t necessarily act like adults)
• Gintama (main character is an adult, his sidekicks are not, but the majority of the cast is adult. Again, comedy, so maybe not “adult” enough lol)
• Cowboy Bebop
• Way of the Househusband
• Gundam Thunderbolt

From my spouse:

• Servant x Service

Not sure if it’s considered true anime, but Castlevania on Netflix was excellent.