Felt quite like a Nolan movie with a lot of potential for analysis and symbolism that went a bit over my head, especially about the onee-san. The stuff about her memories for example. The MC's personality was interesting, I appreciate how you can directly infer the parts of it that are shaped by his parents, environment, etc. Same with the girl from his class; wish the other kids were a little more developed.
His relationship with the onee-san was the highlight obviously, I hope he solves her mystery and finds a way to bring her back to marry her.
Liked it a little more than Mirai but less than Wakaokami.