I am writing a fanfic, I have a skeleton made, and am currently fleshing out small details. The question comes as a result of having multiple protagonists. This is not a trainer fic, so as a result my main characters will not be traveling together around 75% of the time. How do I go about properly portraying all characters at once, how do I give the proper amount of "screen-time"? How much do I dedicate to back story and such? I have 4 Primary Main characters and around 6 Secondary Main characters.