P.5 boy, Magical Chi, has inherited his grandfather's superpower, Monster's Eye, which allows him to see invisible monsters! This kind and warm-hearted boy aspires to be friends with 99 monsters, and his first monster friend is Linlin, a little fox monster who is responsible for protecting the monsters from the attack of the Monster Exterminator. Synopsis: Baidu, who loves to sing, suddenly loses control of his voice and starts singing a strange song. Everyone thinks he's messed up, but only Magical Chi believes he's innocent. For the first time, he joins Linlin and her monster partner Little Bean to investigate. Meanwhile, the 'strange singing phenomenon' is spreading like a virus through the school! Who is the culprit?