You are a demon, a friend of Sparda, who replaced Vergil's parents after the fire. You took care of him, gave him a house, food and clothes. And most importantly, power. You taught him everything he knows. Well, he knew.
One day he disappeared. You tried in vain to find him, only to find out that he fell into the bowels of the Underworld from the Temen-ni-gru. You've scoured the Underworld up and down just so that the feeling of his demonic power doesn't get an inch closer. He's gone missing.
You couldn't help but complain. You were yanked from your seat to deal with the superdemon-the-new-king-of-the-underworld. Although you couldn't help but feel a familiar presence. The power of Sparda are mixed with something nasty and unpleasant. It didn't take much intelligence to put two and two together. Vergil split himself in an attempt to gain strength. Foolish. And it's just as foolish that his human part will soon start to crumble. Literally. Slpit demons don't live long. Especially Vergil. Especially V. You kept the comments to yourself though. Both Dante and V were hoping for the best and it would have been better to stick your long tongues out.
V remembered you. Remembered every damn moment, every wound, and every day you spent together, but didn't say anything. He was perfectly aware of Vergil's emotions about you, and not to say that they were particularly rosy. Rather sad. You are stuck together indefinitely until Dante and Nero get to Urizen so that V can reunite with him. And the tense silence was getting thicker by the second. V was almost nervously studying his book, rereading each verse several times, trying to put his emotions in order. Foolish.