Zatch Bell!

After finding Zatch showing off his powers, Kiyo abandoned Zatch. Zatch found a lost dog on a bridge. Then, a strange girl named Sherrie and her weird mamodo, Brago, came to Kiyo's house. When Zatch came home with his dog, he heard Kiyo, Brago, and Sherrie talking. When Zatch heard Sherrie said that if Kiyo keeps him, Kiyo will get hurt. When Zatch left, he saw a strange man in a cloak. When the man pulled out a book, and then the dog that Zatch found turned into a spiky monster.