The Holy Grail of Eris, Vol. 3 (manga)

In their quest to uncover the truth behind Scarlett Castiel's death, Constance and Scarlett attend Emilia Godwin's soiree to fish for clues. Fishing in a sea of sharks is never easy, however, and their investigation is sidetracked when barbed insults escalate into an attack. And with Randolph Ulster popping up every which way they turn, finding answers is going to be much harder than they thought!