hmm,rather than "just" a dream I'm thinking that this is probably somekind of flashback dream from cat-Mio side, you know,like when she first met with Cat-Ritsu for the first time.
I...*WHAP*Why...OORYAAAA!!That black cat over there! What's with your gloomy expression!? Liven it up a little, eh!!Here! Eat this fish and feel better!!*opening eyes*