Frieren is a modern classic, with some of the best animation I've ever seen & deals with the themes of companionship and regret in a surprisingly mature way. It would be my recommendation for sure!
Strangely (maybe), but Attack on Titan I can't stand, and I didn't care much for any of the Full metal Alchemist ones, but Frieren is one of the absolutely best shows I've ever watched.
Yeah, that's a fair point. I haven't yet watched the 3rd season of Made in Abyss. Have been hesitant to do so due to its reputation. ;)
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Hai to Gensou no Grimgar has both manga, and light novels, that stretch on for many more chapters past the anime. The Manga was good and continues on well from the anime. After reaching the end of that I picked up the light novels to continue on further.
Unfortunately (around novel 13 I think?) the author clearly didn't know what to do with the story and it turned silly and boring, so I moved on to other stuff. :(
Somehow I never got into reading manga, probably a good thing too - I checked my MAL stats and I says I have watched 330+ shows and I know I have been lazy and not rating all of them ...
Full metal Alchemist: Brotherhood https://en.m.wikipedia.org/wiki/Fullmetal_Alchemist:_Brother...
Attack on Titan https://en.m.wikipedia.org/wiki/Attack_on_Titan
Mushishi https://en.wikipedia.org/wiki/Mushishi
Frieren: Beyond Journey's End https://en.m.wikipedia.org/wiki/Frieren