Nia Nal x Brainy
Spoilers below, read at your own risk!
In Season 4, episode 15 "O Brother, Where Art Thou", Nia Nal kisses Brainy, however, Brainy later tells her they can't be together but he doesn't say why exactly it has to be that way. Can someone please explain to me why they can't be together? Is it because they are from different times? (Brainy: future, Nia: present)