Oh. No, I mean—"lusus" is the name of the role, sort of like how you...

[He trails off as that whole "my mom's a boss monster" thing filters through, confusion soon giving way to... not quite realization, but growing suspicion. Frisk had probably meant something else? But if they hadn't, then... then what? Humans don't have lusii, right?

Making a mental note to choose his words much, much more carefully this time, Karkat resumes the explanation.]

I guess it's like saying "parent" for your species. We call them lusii or custodians. They can be all different types of creatures. Did you just say your mom is a monster?