I'm probably 4 year too late, but it looks like something is broken with the file. When I put it into Transmission, it gets "undefined". I don't expect to be fixed, but if other people get the same error, you may just download the 1080p file. Yeah, I know the anime is produced in 900p or something and downloading 720p is wrong, but I left the encode autism game many years ago and I don't care enough anymore.

I wish there was seeds or a batch of 720p ; w;) prays for a seed to come to this old torrent