You

I knew you would only break her heart.

I never liked you. I've always had misgivings about you. But you sweet-talked her into being friends. Showered her with attention, which you knew she'd swoon over.

Soon she couldn't stop thinking about you. Our conversations revolved around nothing else but you. And how quickly you wormed your way into everything that we do.

I knew you would only break her heart. And today you did.

Unwittingly, I did too. As I told her how you just tried to get into mine.