Circumstances Of A Real Villainess

Seria, the scourge of high society, has changed.
Seria Stern, the villainess who made everyone tremble with fear, has grown docile.
In truth, she hadn't merely changed—she was someone else entirely.
The moment she realized she'd transmigrated into the body of Seria, the villainess of a romance novel, she saw her future with perfect clarity and resolved to keep her head down.
The original ending: kidnap and torment the heroine, then have her throat cut by Kallis, the second male lead.
To avoid only that, she settles her bad blood with Kallis first and even heals his arm.
Thanks to that, she's even become engaged to the second male lead—surely everything's turned out well?
At last the original heroine has appeared, so the male lead Lesche should fall for her properly, but...
"I've been waiting all this time to escort her. So—"
Lesche cut through Kallis's words with finality and asked:
"Lady Seria. You should choose. With whom will you go to the castle?"
Something is wrong.
The original story—wasn't it perfectly resolved?