since the previous 2 heroines didn't have negative effects from the loose souls possessing them, i thought that kanon's case might be different in that the loose soul didn't have anything to do with her transparent moments and that there is something in her past that would have made her transparent/disappear.
after all, she is going to have a concert in the same place that a flashback back in ep5 showed her with citron and her reaction before she said the name of the place i think are clues to what is causing her disappearing acts.
oh well, just my 2 cents, everything will become clear in about a week anyway
