The pet spirit in the heavenly book was a fictional creature that was usually described as a soul with special abilities that could sign a contract with the owner to become the owner's help. The pet spirit could bring many benefits to its owner, such as: Increase the pet's abilities: Some pets have unique abilities and the pet spirit can help the owner improve these abilities. 2. Increase the pet's loyalty: The pet's spirit can establish a deep emotional connection with the owner to increase the pet's loyalty and obedience. 3. Increase the pet's strength: The pet's spirit can help the owner to display the pet's strength in battle and increase the pet's combat effectiveness. 4. Special Skills: Some pets have special skills, and the pet spirit can help the owner give these skills more power. Pet spirits were a very interesting fictional concept in " The Book of Heavenly Tales " that could bring players a lot of different gaming experiences.