Mari Morikawa 
Fiancée No More: The Forsaken Lady, the Prince, and Their Make-Believe Love Volume 2 [EPUB ebook] 

Following Diana’s thwarted assassination attempt on Estelle, relative peace returns to Arcaryne’s palace—but not for long. Trickster, the man who had underhandedly instigated Diana, soon reappears, having found another easy high-profile target: House Rainsworth, whose daughter Olivia had once been rumored to be all but engaged with Arcrayne. As Trickster worms his way into the family’s mansion and gains nearly everyone’s unsuspecting trust, the household quickly dissolves into chaos. It is now up to the prince to stop the interloper before he does too much damage.
As for Estelle, she will soon come face-to-face with an old enemy…