Originally, my only main lead was supposed to be Auriella, a fierce demoness who's destined to save her world. But...then I wrote the prologue and her male lead appeared on the page
The more I fixated on him, the more I wanted him to help her grow emotionally, mentally, since she's pretty cold to everyone except her best friend before she met him. I think it's really helped the story as a whole myself, but I'll let you be the judge of that