I am certain that Avery would walk circles around him with insults too. XD Jack would still be nice to him, even if he frowns at Avery a lot. He has this problem- it causes him to give people 8,000 chances before he finally will write them off as jerks.

I think he and C would get along fine. Jack likes a lot of different types of music, and he can appreciate just about any type of music.