The Villainess's Only Ending is Death

I've been reborn as Penelope, the only daughter and adopted child of the Eckhart ducal family, a villainess in a reverse-harem strategy game. The difficulty level is extremely high! No matter what I do, the ending is always death. Before the 'real daughter' appears, I have to somehow win over one of the heroine's love interests! There's my constantly-bickering older brothers, a crazy crown prince whose every route leads to death, a lovesick wizard, and a loyal knight! 'Let's get rid of the hopeless ones first.' “I didn't know my place. From now on, I will live quietly without bothering you.” But why does my likability keep going up the more I draw lines?!