I Want To Steal My Half-Sister’s Fiance From Her, But She’s Even More High-Spec Than The Prince So I’m In A Dilemma!!

I’m Catherine. I grew up as a commoner but it seems that the Duke will remarry my mother, and we’ll be welcomed into their House. Yeah, aren’t we so lucky? I’ll take advantage of this good fortune to snag a lord with good territory, money, and status! I was excited to put this plan into motion but I’m being bothered by my half-sister. What’s more, even though she’s much wilder than I am, she’s getting so much attention in our territory and the noble’s social circles, it’s driving me crazy. If this goes on, I’ll steal my sister’s fiance, the First Prince! … But, isn’t my sister a better, more high-spec catch than the Prince…?