Allen, Lavi, Bookman and Lenalee were put together as a Unit to find Cross. Allen missed the train so Lavi had to go back to get him, and that's when the town ask for help again a vampire, Krory. They find out that he has Innocence.
I'm sorry but you're not going to get a proper answer unless you tell us what Lavi is from. There are a lot of stuff out there that has a Lavi in it. If you're talking about the Lavi from D. Gray-Man then no, I don't think he is but I'm not a 100% sure..... Sorry for the crappy answer.
Allen Walker!! :D -Lavi is awesome too! so is Kanda! X3
he is 15
Todd Haberkorn voices Allen Walker .
It's lavi of course. He is the hottest guy in all anime history. Lavi Rocks. Wrong! Lavi is cute, not hot. Yuu Kanda is the hottest MAN in D.Gray-man.
Fortunately he doesn't. Though it seems like he does in episode 91, Allen operates the ark and brings them back. They weren't dead in the first place, as Cross states- they were only stuck between demensions. :) But the manga is still ongoing, so we never know. We can only pray to God he doesn't die (Hoshino states that she likes Lavi a lot, so it's unlikely that she would kill him off)
They don't really say, but it's probably Allen.
Chris patton .
In it they only have small childish arguments about nothing important. They don't really fight, only with words that are seconds later forgiven. Hope that helped :D
Idk but I really hope they ended up together!!
In my honest opinion, i think that it seems that Lavi might like Lenalee more then a friend or comrade. Thought it seems she might have to hots for Allen, i think Lavi got that wave and seems to be acting more on the basis that hes Allens friend and that's hes the future Bookman, so he tries not to, though i think Miranda might have a small thing for Lavi...so yeah:3
Tsunaida Te ni Kiss by REDA Musician.