How does Roy get to meet Mullet Fingers?

In the book Hoot by Carl Hiaasen, Roy Eberhardt has just moved to Coconut Cove, Florida. He first notices the running boy, who turns out to be Napoleon Leep, better known as Mullet Fingers, while he is on the bus. It is in the opening paragraph of the novel:

Roy would not have noticed the strange boy if it weren't for Dana Matherson, because Roy ordinarily didn't look out the window of the school bus. He preferred to read comics and mystery books on the morning ride to Trace Middle.

Dana Matherson is a bully who torments Roy throughout the novel. Roy becomes obsessed with finding out who the boy is, running with no shoes when he looks like he should be in middle school as well. He tries to find out who the running boy is by asking Garrett, his new found friend. 
In chapter 2, Roy is once again being tormented by Dana and sees the running boy once again. He gets off the bus to chase him into the woods near a golf course. In doing so, he attracts the attention of Beatrice "The Bear" Leep. She warns him not to try to find the boy again.
Roy meets the running boy in chapter 5 when he returns to the outskirts of the golf course in search of him. Roy introduces himself, and the running boy releases poisonous snakes and tells him to leave him alone. When Roy asks what the boy's name is, he replies, "I've been called Mullet Fingers, and I've been called worse." That is their initial contact, even though Roy doesn't see him in this encounter. Later, Beatrice takes him to Mullet Fingers, and Roy learns that Mullet Fingers is her stepbrother.