@Lily_and_frog @resera @Chrishallbeck I presume you're thinking it's a figure of speech in the sense of it being about a song you can hear in your head without needing to actually hear it in the physical world. Well, that's real to me.

And not in the Animorphs sense, because that is in fact not...well, sometimes there are spiders in real life in ears. So earworms *could* be a thing, but...not a common occurrence.