His teammates think he's a huge grump and has no personality... which they aren't completely wrong. He's a pretty reserved guy, but of course, the rookie is gonna try to crack his shell.

No one is really sure why Vin is the way that he is, even he's not sure why. He didn't have a bad childhood or a rough time getting to the show, so why is he perpetually grumpy? Is it because he doesn't let himself have a life outside of baseball? He wasn't particularly close with any of his teammates, had a crumbling relationship with his girlfriend, he didn't have much going on besides being a catcher.

When Romeo was called up Vin didn't expect his life to be completely changed, he thought he just had to build up a workplace chemistry with the kid and move on with his life. Like with all new teammates, he introduced himself and that was the extent of it. But for some reason, Romeo would not leave him alone. At first, he was annoyed, especially with him calling him Vinnie, but over time he became more appreciative of him, and even got concerned when Romeo called him by his actual name and not his nickname. Due to Romeo, he started to do things outside of baseball and discovered more about himself, figuring out why he shut himself away from the world, and finding someone who truly loves him.