I'll Make Sure I Come Out Ahead in This Broken Engagement! And Then I'll Marry My Beloved Crown Prince!

Out of the blue, Second Prince Maury breaks off his engagement with Ashley, the daughter of Duke Norman. However, this is no surprise to her; in fact, it's the golden opportunity she's been waiting for. Fed up with Maury's terrible behavior and poor character, she has been hoping to split with him for a while now. But even a worthless prince is still royalty; to protect her reputation, she must ensure all the fault for the split lies squarely on Maury's shoulders. She sets out to collect proof of his misdeeds, then lies in wait... and now that he's broken things off, she's ready to expose him for the filth he is. The real surprise comes from Crown Prince Eugene: impressed by Ashley's bold takedown, he pops a certain question out of nowhere...! It's a swift death to evil in this royal romantic comedy where karma takes no prisoners!!

(Source: MangaPlaza)