In the end, he said:
“Look, I’m a complete and utter asshole. I have a very, very small heart and I can only care for limited periods of time. 37.81 seconds, to be exact. I’ve timed it with my stopwatch. If I go over that time limit, I get dizzy and puke. I can’t care for other people. And if I wanted to love you back, I’d have to get another heart because my tiny, little one cannot support something as huge and complex as love. But I wanna try for you. Granted, I’ll probably have to gouge out someone else’s heart and add it to my own to be able to do it but I hate other people so I’m sure I’ll enjoy killing for love.”

What does one say to that?

It’s simple, really. So I answered:
“You already have my heart. So, now, love me back.”