Human Pet

Noah always found himself to be a loner in the orphanage and one night tried to run away on his 6th birthday after being picked on again. An adult came after he to try and bring him back, but he was captured by what he thought were giant monsters and forced into a cage on a ship with lots of other animals and most of them were alien to him. He lost track of time rather quickly and wondered how long he had been there... Suddenly, the ship got stopped and boarded by more giant aliens... What was going on?