The Former Assassin Who Got Reincarnated as a Noble Girl Volume 2

How ironic that I, someone killed by a knight in their past life, am now a prince’s guard.
Selena Violette, a duke’s daughter known for her enchanting beauty and cold personality, carries the memories of her former life as an assassin raised in the slums. Crown Prince Evan has singled her out based on her quick wit and combat capabilities, and she joins him in caring for three international students from a neighboring country. The problem is, these students are half siblings and two are aiming to take the other out. Selena thought she was a merciless assassin, but once she experiences protecting another, can she use her assassin skills to save rather than kill?

[From Cross Infinite World]