WELL Rei is indifferent about the swords to be honest! She outwardly was rather (unsure) about them because there was so many of them ha ha ha..... though inwardly she was pretty much "yeah one of them is a traitor"

so she was pretty much laughing inwardly because she knew it would have to happen eventually. Post-game she doesn't mind them as much (at least, most of them) o o p s.