Answer:
Rufus was a better friend to him than LJ Jones.
Step-by-step explanation:
At first Kenny believed that Rufus would become the new target of the other kids’ teasing. He felt that he wouldn't be the bullies' attention anymore as Rufus would take over his place.
However, once they became friends, his perspective about Rufus changed and realized that Rufus was a better friend to him than LJ Jones. This can be seen in these following lines "To Kenny’s surprise, he and Rufus Fry become close friends. Rufus is a much better friend to Kenny than LJ Jones, who is always trying to trick Kenny."