Who? You mean one of our main characters doesn't have a name? Yup. All we really know about this kiddo is that he's Mrs. May's brother, who first tells her the story of the borrowers. Oh, and he's staying in Great-Aunt Sophy's house while he recovers from rheumatic fever that he got in India.
Okay, so here's the question. Why in the world would such a main character not have a name?
Well, for one thing, it keeps the boy mysterious. And boy is he ever mysterious. Just check out Mrs. May's description of him:
"And yet"—she looked into the fire—"there was something about him—perhaps because we were brought up in India among mystery and magic and legends—something that made us think that he saw things that other people could not see; sometimes we'd know he was teasing, but at other times—well, we were not so sure…" (1.34)
Um, spooky much, Mrs. May? His lack of a name and his upbringing in India tip us off early that this is not your average kiddo. Plus this description sets the stage for the introduction of our favorite "little people." It makes perfect sense that he's the first to see the borrowers, because he's got special, supernatural vision. He can see things that others can't.
As much as the boy often comes up with magical stuff, he is also totally completely and totally human. And humans in the novel are against borrowers just as much as borrowers are against humans. The two have such prejudice against each other that we wouldn't blame you for thinking that they'll never see eye-to-eye.
Just take, for example, the first meeting between the boy and Arrietty, in which it's clear the boy just does not get this whole borrowing thing:
"Borrowing," he said after a while. "Is that what you call it?"
"What else could you call it?" asked Arrietty.
"I'd call it stealing." (10.9-12)
To Arrietty, that probably sounds pretty harsh. But the boy's got a point. Or at least, according to the rules of the human world, he does.
Of course, as Arrietty and the boy learn about each other more, that initial prejudice drops away in favor of friendship. In fact, that friendship grows so strong that the boy becomes a borrower of sorts, himself.
He becomes the family's provider (he brings them furniture from the dollhouse) and protector. He stands up to Mrs. Driver at the end of the novel, completely reversing the earlier scene where he misunderstands Arrietty's family's actions as stealing:
"They are nasty little crafty, scampy, scurvy, squeaking little—"
"No, they're not," he put in quickly. (18.72-73)
Way to save the day, buddy. Homily, Pod, and Arrietty owe their lives to the boy, who risks personal danger to save them from the rat-catchers' poison. So you have to hand it to him. He's chucked the prejudice he's inherited from other humans out the window, because he knows the borrowers aren't so different after all.
Then, although Mrs. Driver is holding him back, the boy escapes her clutches to set his new friends free:
My brother slid through the barely opened door and it sighed to behind him, closing out the noise. He took a few steps on tiptoe down the dark kitchen passage and then ran […].
He was not, as I have told you, a very strong little boy, and he was only nine (not ten as he had boasted to Arrietty) but, with two great blows on the brickwork, he dislodged one end of the grating. (19.65,67)
Talk about going from zero to hero. The boy saves Arrietty and the day. And it's a good thing, too, because getting rid of those feelings of prejudice opens up a world of opportunities for borrowers and humans alike, not to mention the door to an amazing friendship.