This is Solo Ganti and Daolo Danti! They're light and darkness. :3
I'll explain both of them but not to much in details since they're still WIP characters. XD But let's put it so you guys can understand...
Both are from a world called Luvlot, It's a planet of Assassins and Love. The Assassins of Love gain power by protecting things they love, And it's very girly, yada yada.
However, Due to their obsession of being peaceful, they had to battle their own darkness, as no matter who you are everyone haves a darkness within. They created a mortal made god invention that can suck out the dark emotions of people, But in return... They would reside in the world. For 150 years, They've been doing that once they reach a certain age where their dark sides begin to show. It became a tradition, but what they didn't know is they were making a mistake by letting darkness consume the planet slowly over the course of time, And since they can't die... They only grow while Luvlot's assassin's fall and dies by age.
Solo Ganti is an Assassin of Love, and also the Prince of the current Era, While Daolo Danti is the dark side of Solo.
Daolo landed up placing his mark while joining the evil realm group known as Anti-Love, A dangerious and evil group against anything love-like in the Kingdom of Sorarch, a Kingdom that formed of darkness over the 150 year course of time. And Daolo would have made enemies of Luvlot by killing Solo's mother and torturing his brother. Saying it should have been his life, not the make believe Love Knights.
And this is the story between the two of them, How Daolo swears he'll kill all of them along with Solo, while Solo merely wants to find peace and avoid him. He even became an asshole due to a curse, to seal Daolo away along with his power. But once Solo opens up his heart, Daolo becomes free.
And that's all I can share. o: