[Alice has probably seen Sebastian around. He quite possible assigned her a hotel room on the day she arrived. She's likely spotted him down in the hotel lobby, managing the reception or seeing to the upkeep of the hotel. He's very... adult. Seems kind of strict and no-nonsense, probably.
Now, because Sebastian works in the hotel, it's only a minute after Alice has written her piece that he exits the hotel and approaches her.]
Miss Alice? Regarding what you wrote just now. [Also hi or something.]