You've got a free invoke on that aspect, and the aspect will last until Antorell Overcomes it or until the end of the scene (unless appropriate for it to continue).
"You harpy! Princesses don't behave like that!" Antorell is furious, and retreats into the woods to Quickly search for his staff before the furious lady beats him with her stick.
Antorell continues to try Quickly searching for his staff and ignoring Thursday, and I think that "honeymoon" bit is an excellent defense against his success.
Before he can do anything fancy with that stick of his, Thursday darts in and knocks it away again. "You're not getting that back until you answer my questions."
"A clever invention of mine! Elegant, isn't it?" He loves to gloat. "I call it 'Withered on the Vine.' The cure is very traditional, really: Marry me."
but I wasn't expecting her to casually consider killing him
I mean - she's not being caustic just for the sake of it. This is also genuine curiosity - does it work if she kills him afterward? Is this a workable solution?
"You know, I think it wouldn't have time to kick in..." he pauses for dramatic effect before Flashily Creating Advantage (aspect, self: "not to be trifled with"). "...before my father led the Society of Wizards to raze your kingdom in revenge. So you'd get to watch before you died!"
Antorell grimaces. "Princess, this is ridiculous. I won't tell you what you want to know, and you're wasting your sister's time as well as mine." He looks like he ate something bad. "Find the invisible castle. Bring a friend, if you can make any with those manners. I need her alive as much as you do, middle child."
"Now run along and let me rustle the bushes in peace. I'm sure we'll meet again, love."
Thursday rolls her eyes. "That sounds like a load of horsewhack to stop me from forcing some answers out of that slime you call a mouth. I'm going to need some proof you have any idea what you're talking about."
