I release the curtain and turn to look at her. There is no mistaking the misdirected anger in her features. She's envious of Ivy. A confirmation that she’s too dangerous to have around my wife.
"She was going to take you away from me," she says. "I had to do something. I just wanted to make her hate you. So, I hired that courtesan who used to work for IVI to lure you away at the gala and seduce you. All that was supposed to happen was that Ivy would come out of the bathroom and see you together. That was it. Nobody was ever supposed to get hurt."
I pace a few steps across the room, and Mercedes rushes to cry out the rest of her confession.
"I know it was a stupid idea. I was naïve to think I could trust that woman. I didn't know she was one of Abel's regular conquests. He used to meet with her at the club here until she was shunned by The Society. I didn't figure that out until after the fact. He paid her for information about the members of IVI, and when he found out what I'd asked her to do, he was the one who gave her the poison and the antidote. He put her up to it and paid her three times what I did. They double-crossed me, Santi. I had no idea they would put you in harm's way. If I had, I would have stopped it. You have to believe me."
"How can I believe anything you tell me?" I turn my back to her and shake my head. "How can I believe any of what you're telling me now is even true?"
"Because she told me so herself!" Mercedes shouts.
"When you were beating it out of her?"
A long silence follows my question and then a shaky breath. "It wasn't like that. I was fighting for my life. I didn't mean to kill her, but I had no choice. It was either her or me."
When I collapse into the chair, Mercedes starts to sniffle again.
"Would you rather it was me? Is that it? Do you wish it were me who was dead on that floor?"
"What I would have rathered was that you never lied to me at all!" I roar. "You betrayed me. You schemed. You nearly fucking killed me. My own sister. Do you understand that?"
She sucks in a sharp breath, a fresh wave of tears falling as she watches me pleadingly. "I would rather die than hurt you, brother. Please believe that. If nothing else."
My throat is tight, stomach tied up in knots when I look at the girl who used to follow me around constantly as a child. The one person in my life I thought I could always trust without question. But right now, her every word, every tear is just salt in the wound. It feels like I’m being torn in half by this decision, her betrayal. It’s an agony unlike any I’ve ever known.
I know what I need to do for both our sakes. At this late stage, my harsh words will be of no benefit to Mercedes. I could verbally eviscerate her, and it would make no difference because this is the monster I've allowed her to become. I've watched it happen. She's been coming unglued since the deaths of our father, Leandro, and subsequently, our mother. Lost to her grief, she has turned into a shallow, manipulative, hateful shell of a woman. A reflection of myself, if I'm being honest. And while I can accept that I am who I am, I can't accept that fate for her.
I won't allow her to destroy her life or anyone else's any longer.
"Get in bed and try to get some sleep," I tell her.
"What's going to happen now?" she croaks.
"Now, you are going to sleep," I answer flatly. "And when you wake up, you will start fresh."
She looks relieved but hesitant. Regardless, her exhaustion wins out, and she does as I ask, pulling back the covers and curling up to sleep. For a long while, I remain in the chair, unmoving. Frozen by the understanding of what it is I must do. I can't have her in my house any longer. I can't have her under the same roof as my wife and my future children because it will be impossible to protect them both. Mercedes has made her bed, and now she must lie in it.
It is the hardest decision I have ever had to make when I drag my phone from my pocket and dial a familiar number.
He answers on the third ring, greeting me by my first name.
"I'm ready," I tell him. "I need it to happen now.”
Three hours later, Mercedes stirs from her sleep, gasping for air as she bolts upright, clutching the blankets to her chest. She seems to sense the danger lurking in the corner of the room, and her eyes move to the dark figure sitting opposite me in the shadows. Watching. Waiting for her.