I watched the film Mind Game (2004) today. While it's not necessarily dark/edgy in any sense (honestly, I'd say it's more on the lighthearted side of things), I still do feel like it is, in the end, a movie that will resonate more with adults. What makes the movie unique in my eyes is that it often shifts between different art styles, usually unexpectedly so. It makes the whole experience feel a lot more psychedelic. In the end, the movie's all about second chances, about life, the interconnectedness of things, etc.. Perhaps those themes sound somewhat like standard shonen anime-tier fare, but I don't know, man.. I don't feel like kids will resonate very strongly with that whole "loser who missed a lot of opportunities but finally tries to turn things around" theme. Teenagers perhaps, but.. eh.
Also, apparently Satoshi Kon was a fan.