Nero is a half or less breed of Devil/Demon and Human. In the game, Devil May Cry 4, you play as him and Dante. You never learn of his past or anything other then the fact, Nero is somewhat linked to Dante.
Now in a book by someone in Japan, he said that Nero was the son of Vergil when would be a good reason why Vergil's sword and Neo Angelo works with Nero in the game. But sadly, there's no way to know if it's true or not.
In Fanfics(by me and Amia), Nero is the son of Lora and Vergil.
In Elyasia, Nero came to the realm after a few years of no word for his aunt Tara nor his mother. He knew nothing of his father and sadly didn't care to know, as he was mostly worried about Lora.
Love Interest: None in this fanfic... sadly.
Fanart and game shots of him. I own nothing.