Cece has a hearing loss at age 4. She can already talk, and learns to read lips, but only hears clearly via a clunky Phonic Ear device that straps to her chest, plugs into her ears, and makes it impossible to blend into a regular class. Her alter ego, El Deafo, knows what she ought to say to speak up for herself, though she often struggles, and the "one true friend" she seeks would be El Deafo's perfect sidekick: she wouldn't mind the hearing aids and wouldn't treat Cece as someone "special." 
 The graphic novel format is particularly apt here. When she has lost her hearing but doesn't know it yet, you, the reader, can see the blank speech bubbles surrounding her, with no words in them. When her hearing aid battery is dying, you can see the words fading into nothing. When she describes the difficulty of watching TV or reading lips, you can see just how problematic it is when someone faces away, has a mustache, or switches to voiceover. 
 This felt so poignant to me. I've had all the kinds of friends in this book, and I've even been Martha, the super-sensitive friend. I've been in those gym classes, and felt that "I hope they don't notice I'm different" feeling, for different reasons. I thought this was very well done. For those that wondered about why she depicted her characters as rabbits, she answered that on her Goodreads profile: "Because rabbits have big ears. I thought it would be a perfect visual metaphor to portray myself as the only rabbit in a crowd of rabbits whose ears do not work. Also, as a kid, I felt very conspicuous with my hearing aid cords going up to my ears...and showing those cords going way up over my head into my rabbit ears is pretty close to how I thought others must be perceiving me. Finally, you can't top rabbits for cuteness!" 
 Raina Telgemeier and Wonder fans will want to take note.