I'm having trouble because the frivolous Duke's son is spoiling me, saying "I'll absolutely make you fall for me."

"How about it? You've started to like me by now, haven't you?" "That's a nuisance. Please stop fooling around!" At a certain evening party, after I declined his invitation to dance, I became the object of obsession for Nils, the eldest son of a prestigious ducal house and a profligate womanizer. Despite his frivolous attitude, he showers me with affection saying "I'll absolutely make you fall for me," and I continue to give him the cold shoulder today as well, stubbornly repeating that I "hate" him. ——Because I, the daughter of a poor viscount family, must not fall in love with him. ※This is a safe and heartwarming happy ending. ※This work is posted as-is without additions from a piece submitted to the "Anonymous Short Story Heart-Throbbing Project" hosted by Minagumo Kō. ※It is cross-posted on Kakuyomu.