Review Detail of Mador in I Know the Secret to Surpass Level 100

The world is generic, there are constantly characters that try to be mysterious and do something that is commendable for the protagonist even if they are "enemies", the protagonist gets things because he does and basically achieves his goals because the world wants him to achieve them. The more it bothers me is his personality as if he were a child of 10-12 when he is said to be 18 and more if he is supposed to spend the last years alone.