๐I recommend the following books: 1. "Familiar Evolution: I Have a Portable Space": The protagonist has a portable space in his hands to nurture various contracted beasts. 2. [Contracted Magical Beast: The protagonist is a magical beast master. He signs a contract with a magical beast and becomes a legend of an era.] 3. "Familiar: Summon the Zombie T-rex at the Beginning": The protagonist awakens the system, allowing the spirit of his familiar to evolve into a Thunder Zombie T-rex. He then signs a contract to subdue various strange magical beasts. 4. [Magical Beast Spirit Master: Humans can summon their own magical beasts with summoning skills. They can also find a variety of magical beasts in the world and subdue them.] 5. [Unlimited Enhancement of Monsters: The protagonist contracts a mutated beast, cultivates it, and evolves it to the highest form.] I hope you like my recommendation, Mwah ~๐