MIB is not a criminal by lexieultra

Here are some simple ideas that have finally come together.

The MIB is not a prisoner in the criminal sense. Jacob and the MIB were once allies who discovered the Island and understood it's power and potential for corruption. They decided to protect the Island together -- protect it from the outside world. The superhuman power they gained on the Island is what they use to do their job. But after centuries of duty they have become bored. Jacob is looking for a successor, and the MIB doesn't care anymore and just wants to leave.

But Jacob still has some sense of duty left and is therefore compelled to keep the MIB from leaving the Island and spreading the Island's corrupting power.

The Game is their way of passing the time. Both know they can undo each others moves via time travel so the only way for them to enjoy their time on the Island is to invent a Game with rules for them to follow regardless of their ability to cheat. The Game is a way for them to exercise their godlike abilities. Sort of a way to govern each other.

Notice the lack of emotion in their conversation -- "Just let me leave", "As long as I'm alive you can't leave", "I will kill you some day" etc. Clearly mutual respect and a sense they have been doing this for a long long time. Their abilities are equal and they have had the same conversation many times before.

Both remember why they decided to stay on the Island and protect it from corrupting the world but the MIB just doesn't care anymore. He is tired of the wine and just wants to shatter the bottle.