Well, the future Count Scarlet, in this context. It's just a slightly oblique way of calling him Remilia's fiancé without repeating that specific word, which Marisa had just used herself (albeit in the opposite gender) a short while before. Conversational streamlining.

(Besides, his Karlsland title isn't something that comes up very often in the day-to-day at home, so even if Sakuya knows about it, it wouldn't be uppermost in her mind; he pretty much only uses when he's dealing with somebody in the outside world who response to having titles thrown around, or who used it first, like Admiral Sugita.)

--G.
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Benjamin D. Hutchins, Co-Founder, Editor-in-Chief, & Forum Mod
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