So, I don't remember anything other than the world building. Basically, this is a world where you get classes when you get a certain age, Each time you get a class, you gain a level. Like a normal person is lv 0 If he gets class 'grass eating bug' he becomes lv 1 bug. In the rare case scenario he awakens 2 talents, say he gets a bug and a ninja, then he gains two levels, making him lv 2, The highest a person has been able to go is lv 10. MC has this tool or something which gives him a new class everytime he uses it, hence he gains a level in almost every chapter. I just remembered, this tool i just spoke of, MC gains a new class every time he marks his attendance in class