@REDS It's explicit that the age in which the condition expresses is highly variable (Yuki is very rare in having been *born* as Catulus, as Anna has repeatedly noted) so that doesn't mean anything by itself.
Her fake ears and tail already came up in a previous volume extra anyway, the rest of the cast just wasn't present then.
lovable morons, the whole lot of them. Yes, even Anna; much as I'd wish she'd dial down her flair for the dramatic, her heart is good. Poor Yuki's never going to recover from the professor's cannibalistic experiments.