Manipulative as it was, Vincent had the thought that despite already buying Maya's loyalty, keeping his promise to be nice to her indefinitely as planned would only help his cause. That way, she would be less likely to care what she had been involved in when she did eventually find out.
Not that he truly thought she would care much in the first place. Someone as angry and hurt as she was who had constantly been let down by the world wouldn't care about it burning.
He was going to be nice to her anyway because he wanted her to be happy. This was merely an added benefit. He didn't have to feel guilty about doing something he already planned on doing.
Once their work for the day was done, he put his backpack on his stomach so he could give her a piggyback ride back to the life raft. It was a bit of a workout because of how far it was but she truly didn't weigh that much.
Maya was tiny. Delicate. Breakable.
