If you loved Book Girl, try Legend of the Galactic Heroes: Die Neue These - Intrigue 1
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.
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Legend of the Galactic Heroes: Die Neue These - Intrigue 1
What they share
Both films are directed by Shunsuke Tada, and they sit in Animation / Drama territory. If that's the register that drew you to Book Girl, the second film will land in a comparable space — through a different lens.
What Legend of the Galactic Heroes: Die Neue These - Intrigue 1 is
You pilot a spaceship in a galactic war, but then rival factions clash, and the series leaves viewers with Reinhard von Lohengramm's ascent.