Sharing a Body with the Villainess to Conquer the Heroine

I transmigrated into the body of a villainess young lady, and the original owner is still living inside me. What should I do?

I planned to take her far away from the protagonist and lie low until the end.

But I accidentally conquered all the heroines.

Angel heroine: “You saved me. My soul belongs to you.”

Yandere heroine: “Interesting. You two are both mine.”

Me: “...Can I still go for the doom ending if I start now?”

[Also known as: Survival Guide for a Villainess with Two Souls; After Failing to Avoid the Bad Ending, I Conquered All the Heroines]