This, + general storyline and execution of the product made it the first game I found myself to be really involved emotionally with. Say, when I picked up the second game and met an important NPC from the first, I literally felt like I've just rejoined with an old friend. By the third game I actually printed out a photo of my character and her entire team. It's crazy how deep a good video game can touch you.
Oh, and I spent 10-15 minutes thinking heavily about morality and consequences just to choose the right ending...