In Devil Boy Quest you can learn skill not only by Level up or story, you can also find lots skills in books!
Good luck hunting books!
Most of them easy to find but you need to check for who was that book since you have to chose who will read it, plus there a non skills book that tell you long history, be sure to avoid them. (Lexar don't like read book so keep in mind)
Lexar unmotivated study rule: "Read some forget some, Read lots forget lots, didn't read any didn't forget any, so Don't read any!"