That would be his majesty King Asgore Dreemurr of the Underground, yes. [She looks amused.] I wouldn't be terribly concerned about it if I were you, dearie- you're neither a citizen of the Kingdom of Monsters nor anywhere near its' legal boarders, it isn't as though he has any proper jurisdiction here.

[He's relaxed enough that even people actually under his rule could get away with being casual with him, Muffet's just polite on general principles. She smiles warmly at Toriel.]

Well, it's always a pleasure to have such a supportive customer- I'm sure they were delighted to do business with you.