Putting aside introduction, overall the OVA is average, nothing stands out about it, but it does what an OVA is suppose to do, animate a bits of the game for the fans of the game. In this case, the OVA covers essentially the ends of the different scenarios, which is probably why everyone finds it soooo confusing.
Overall, if you played the game, it's not a bad way to kill 90 or so minutes, it is kinda nice to see the game you've played come to life with an upgrade in art(the game came out in 1998. Otherwise, I highly doubt that you'll find it all that enjoyable unless you wanna experience a small part of the piece that made Key Key without going through the hassle of playing the game.
