Apsu, a water-fox, was found along a stream during one of Double's travel's for more bishies. or rather...Apsu found him. He wouldnt stop following the hunter and tigerfox as they went along their way; though he wasnt a nuisance but more of help. He didnt talk much but liked to mimick sounds and actions that other bishie's made, which made him the perfect bait. They tried to reward him with food and part ways but instead he decided to follow, having heard about the Kingdom through other animals, and wanting to find a companion.

not much is known about Apsu's past but from what he has told the hunter on the way back he is a spirit of a fox that had drowned in the river reborn. He had been waiting along the stream for someone to find him, and felt that Double was the one who would be the one to save him from lonliness.

Apsu has been adopted by someone who was quiet enough to keep a fox spirit calm yet good company; Dezso, the scriptor.