Princess of Neighboring Country

In order to save the princess of a neighboring country who was bitten by a crocodile, the boy traveled a long distance to the nearest hospital, but accidentally lost the princess and the prescription for treating the crocodile bite. The male protagonist had vague memories of these for some reason, and the male protagonist's physical condition began to deteriorate for some reason. Despite the difficulties, the male protagonist did not give up on finding the truth about the missing princess.