Forsaken Marquis's Daughter Is Loved to Pieces

After her mother passed, Lucia was left with a family who had barely a care in the world for her. Her only value to her father and stepmother was that the second prince had chosen to marry her. But all it took for her to lose him too was a little temptation from her younger sister Nina. Not only has Nina been revealed to be with child, but the prince now wishes to wed her instead! When Lucia is about to lose all hope, she meets the kingdom's rumored archduke...

(Source: Manga Plaza)