Who goes on a journey with Ponyboy in The Outsiders?

Johnny is with Ponyboy during his journey.

Ponyboy is a greaser, and the greasers take brotherhood seriously.  Pony comments that the value of a gang is in members looking out for each other.  Ponyboy and Johnny are together in the park when they are attacked by Bob and his friends.  They are Socs, and they often attack without provocation.  The two gangs fight each other.  In this case, though, the Socs attack Johnny and Ponyboy because they saw them with Bob’s girlfriend at the movies.

Bob and his friends attack Pony and Johnny in the park.  Bob almost drowns Pony in a fountain. 

I ducked and tried to run for it, but the Soc caught my arm and twisted it behind my back, and shoved my face into the fountain. I fought, but the hand at the back of my neck was strong and I had to hold my breath. I'm dying, I thought, and wondered what was happening to Johnny. (Ch. 4)

Johnny reacts instinctively, taking out his switchblade and killing Bob.  Johnny and Pony then go on the run.  They are afraid that they will be charged with murder if they stay put.

With Dally’s help, Pony and Johnny hide in an abandoned church outside of town.  They adjust their appearance by dyeing and bleaching their hair, and they entertain themselves by reading the Civil War novel Gone with the Wind.

Johnny sure did like that book, although he didn't know anything about the Civil War and even less about plantations, and I had to explain a lot of it to him. It amazed me how Johnny could get more meaning out of some of the stuff in there than I could--- I was supposed to be the deep one. (Ch. 5)

Johnny and Ponyboy’s adventure gets even more serious when a group of kids on a field trip stop by and get caught in a church fire.  Pony, Johnny, and Dally try to rescue the kids.  They all get hurt, but Johnny’s injuries are the most serious.  He dies in the hospital shortly after they return home.