LogFAQs > #971156629

Something weird about Vergil is how he doesn't try very hard to conceal his fear of Nero. Vergil is usually pretty happy to talk himself up and try to cross whatever bridges he comes to. With Nero you don't see much of this.

Look at his retellings of the other games. He claims to beat Dante twice in DMC4, twice again in DMC5, claims to beat Doppelganger which is a shadow version of Dante and you gotta wonder if his OC Red Vergil was at least partially inspired by Dante. These are mere defeats.
In DMC5 when he fights Cavaliere Angelo and Artemis, there's no rescue cutscene to bail Lady or Trish out, Vergil's has no issue claiming he could kill them just like that.

Nero though? There's no depiction at all of Vergil defeating or even initiating a fight with Nero. In the actual story of DMC5 Nero is the one who coaxes Vergil into fighting him. Vergil - no doubt with his decision making impaired by all the meteors that just fell on top of him - mumbles something about how beating Nero secretly counts as beating Dante and proceeds to charge Nero.

Vergil jumps through some hoops to ignore Nero. His retelling of his time in Fortuna avoids the issue. His DMC4 story is so transparently fake that you have to wonder if whatever really took place sits alongside his time as Nelo Angelo as something he's desperately trying to forget.
Speaking of Nelo Angelo, that's a name. Nero is an Italian word meaning black, Angelo means angel, you put those two words together you'd get two words put together. Not what happened. Instead Vergil is inexplicably named Nelo Angelo and you know it's canon because Griffon in 5 acknowledges the L in his name. Did Vergil change his alias to contain a made up word because he was aware of Nero's existence, ashamed of whatever happened in Fortuna and desperately wanted to avoid association with both.

Another possible cover. Vergil used to wear a blue coat but now wears black. Perhaps this was a ploy. This way, when people used the word or name Nero around him he would be able to feign confusion and pretend they were complimenting his fancy new coat.

Finally in the boss fight, you know what happens. You're 25% into his health bar, maybe you've buster grabbed him once. Regardless Nero will say "Feeling accepting yet?" and Vergil will say "Of your existence? Or your strength?" which tells you first that Nero even existing is something Vergil dreads. Vergil treats Nero like he who must not be named, unless it's around Dante who was never going to fall for any of Vergil's ruses or schemes. Vergil is absolutely terrified of Nero.
The second part of Vergil's line is Vergil's facade shattering. He concedes, 25% into the fight that Nero is strong, formidable and most likely going to defeat him. This signals that the other 75% of the fight will be fought against a dejected Vergil who has already given up. Vergil is taking a poignant moment to reflect on the events that lead up to his world beginning to grow dim at the top of a tree with two Overture bombs tied to him that he for some reason hasn't tried to remove, with a little flying robot fist repeatedly punching him in the jaw, intermittently being pelted with exploding bullets all while his son keeps saying "Ridin' high! Let's get airborne!" and barely registering his attacks as a threat. "Why is the song called Silver Bullet I'm not a werewolf..." Vergil might wonder as his motivation leaves him once and for all.

V kinda reminds me of the guy from The Quiet Man, maybe Vergil likes that game.