If you loved Orange: Future, try Steins;Gate: The Movie - Load Region of Déjà Vu
A bridge between a film you've already seen and one most people haven't. Here's what they share, and what the second one does that the first one doesn't.
What they share
Both films are directed by Hiroshi Hamasaki, and they both carry the foreign gem, tender mood tags, and they sit in Animation / Drama / Science Fiction territory. If that's the register that drew you to Orange: Future, the second film will land in a comparable space — through a different lens.
foreign gemtender
What Steins;Gate: The Movie - Load Region of Déjà Vu is
Eternal Sunshine meets Back to the Future. Rintarou fades from reality after extensive time travel. Kurisu carries the film.

