Cross-Dressing Villainess Cecilia Sylvie, Vol. 3 (manga)

"Cecilia Sylvie's plan to disguise herself to steer clear of every death flag was going so smoothly...until Dante found out her secret! And although she manages to avoid the sudden death flag by using his identity as a bargaining chip, their abrupt closeness causes Oscar and Gilbert to pry into the change in their relationship. Can she keep them in the dark--even at the cost of her bond with them?"--