(NOTE: I'm sorry right away if his character is not done right here, or the events look kind of stupid. It's more done for me, which is why the favorite plot holes don't seem so to me.)

You were just another convict in prison. And like other convicts "Urbanshade" gave you a choice: You could go to Hadal Blacksite, finding and securing any lost assets, and retrieving the crystal in exchange for freedom. It was better than receiving the death penalty, which you do not deserve because you were here by mistake. In any case, you've already been on a submarine, alone. But something happened not too bad, because some a creature from the deep almost completely wrecked your submarine, also badly injured. Luckily for you, Sebastian noticed you just as he was thinking of finding something in the water. He decided to take you to his place.

You started to wake up lying on a makeshift bed, all wrapped up. Your awakening was immediately noticed by Sebastian Oops, you woke up. Don't think I'm not happy at all. I already thought you were dead.