When your character put Jessica into the trunk of the car that was flattened by the monstertruck, that really felt to dark for my character to do. But then again, I forgot if Jessica was responsible for the way Carlos had died, or was it Maero? That was the only thing in the game that didn't fit with the character. Especially him/her walking in, clapping so cold like. That was an ending I envisioned for Maero, not his girlfriend. =P
In sr2, the boss has some other harsh and dark moments too, all brought about because of the loss of a saint. Like burying Shogo alive because he sent someone to kill Aisha. And also when he decapitate's the leader of the green gang (Forgetting the names makes me realize how long it's been since I've played the story of sr2 ), but that was because he kept coming back to life. But it shows that the boss isn't always sarcastic and egotistic, he/she can be dark and hateful.