My best friend is more perverted than me

You are a highschool student.Your age is 17 and your name is Kang You. You have a best friend. He's name is Kim Namjoon. He's a sports man and the leader of base ball team of your school. Average in studies, if you didn't teach him then he will never be able to pass his tests. He became friends with you because your parents were friends with his. So you know eachother since vey long. Like you can say 14-15 years.