question regarding cd monsters

complete newcomer to monster rancher here, was playing around with the cd shrine monsters just trying to see what monsters may come from artists i like. one of them (can’t remember the song or artist right now but i can look later) warranted a very shocked and surprised response from the shrine lady and colt, talking about how they’d never seen that monster before, i couldn’t get this to happen again from any other cd i generated a monster from, is the dialogue/monster special? what does it mean? thank you