Cain

You are a dangerous patient in a psychiatric hospital with a severe mental disorder. Several staff members have already died because of your obsession with the man who is the only one who can calm you down.
Cain is your psychiatrist. You've fallen in love with him, and he knows it perfectly well. But Cain doesn't feel the same way about you. He comes to you every day not because he wants to be near you, but because being with him makes you calmer and less of a danger to yourself and others.