What's your favorite way to develop complex characters in RPGs?

[1stop]

The development of characters is rather complex in RPGs. From their backstory to personality traits, every detail counts. Making your characters relatable is not that easy but it makes the game even more enjoyable. What constitutes a memorable character to you?

[Demonskeith]

Try to come up with a good story with good support characters to make complex characters all the better.