Mona Ramouni's fingers fly across the text as she proofreads yet another page of a calculus textbook to be published in Braille -- with her guide pony sitting patiently by.
It is dull work for tiny Cali who serves as Ramouni's eyes through a world she cannot see, and the pony keeps butting her head into Ramouni's chest.
"Cali! Stop it," Ramouni exclaims, but she can't keep the pride out of her voice when she realizes what the pretty brown pony with a soft black mane has gotten up to.
Rolling back her thick lips, Cali has grasped the tab of the zipper on the bag of treats Ramouni carries around her waist and is slowly pulling it open with her teeth.
"She knows which part has the carrots," Ramouni says in amazement. "She's really smart."
Cali is just one of a handful of miniature horses in the United States known to be used as guide animals for the blind.
Weighing in at under 100 pounds (45 kilograms), miniature horses are about the same size as a large dog but are much stockier and can help support people with mobility issues.
They also have significantly longer life spans -- they can live and work for more than 30 years while guide dogs are usually retired by age 12 -- but require much more care and bear a far heftier price tag.
Cali is the first guide animal for Ramouni, 28, a devout Muslim whose parents -- Jordanian immigrants -- would not accept a dog into their home.
Dog saliva is considered unclean in Islamic teaching, although dogs are permitted to be used as work animals, such as guards or shepherds.
"There is a saying of the Prophet Mohammed accepted by most Muslims that the angels do not enter the homes where dogs are," said Dawud Walid, director of the Michigan chapter of the Council on American Islamic Relations.
While several prominent scholars have determined that guide dogs are acceptable under Islamic rules, it remains a cultural taboo for many Muslims, he explained.
Ramouni says her parents aren't fond of animals in general, although they did let her have a pet rabbit and are warming to the pony who lives in a small enclosure in the yard of their tidy brick home in Dearborn, Michigan.
And after some initial trepidation about how their daughter would fare with only a miniature horse to watch out for her, they have begun to trust that Ramouni will be okay on her own.
"My whole world and my whole outlook on stuff has changed, because I feel that there are a lot more possibilities," Ramouni tells a visiting reporter.
"Before Cali, I didn't feel like I could go places on my own, although theoretically I probably could have."
Ramouni was taught as a child how to guide herself with a cane, but never really took to it. With six siblings, there was always someone around to take her by the arm.
She began looking into guide horses on a whim, becoming more determined to make it happen every time someone told her she couldn't -- or shouldn't.
There was the neighbor who tried to get the city council to deny her a permit for Cali's shed. The nasty e-mails from people attacking her family's religious beliefs.
And then there was all the work it took to find a trainer, find a horse and learn how to trust and care for Cali.
Ramouni bought the three-year-old former show pony in October 2008 and sent her to professional trainer Dolores Artse, who spent seven months teaching Cali to tap her hoof to point out obstacles, get in and out of cars and buses, and even pick up misplaced objects.
It generally takes six months to a year for the relationship with a service animal to solidify and Ramouni's first six weeks with Cali have been intense.
"I'm working with Cali. She's working with me. We're sort of figuring each other out," Ramouni says.
"She is the most awesome little horse. If she can do it, if she thinks she can do it, she will. If she feels that there is a possibility for her to do it, she will try with all her heart."
Cali is also a show-stopper: they can't go anywhere without people stopping to ask about her.
And Ramouni, whose sisters used to call her antisocial because she would spend hours alone in her room, has found that she has become "more involved with the world... and more visible to the world" because of Cali.
That is the intention of the Americans with Disability Act, which protects against discrimination and requires that businesses, such as restaurants, hotels and stores allow entry to service animals.
But proposed changes to the act could narrow the definition of service animals to "a dog or other common domestic animal."
Not only could Cali be turned away from businesses -- like the McDonald's down the street from Ramouni's office -- but the city of Dearborn could also decide to lift the zoning waiver that allows the horse to live in Ramouni's yard.
If that happens, the city will have to send someone to pry Cali's bridle from her hands, Ramouni says.
With Cali at her side, Ramouni can do simple things most people take for granted like go the store, sit in the park and listen to people going by, or take the bus to work. She also hopes to get a doctorate in child psychology and open her own practice.
"I just basically want to have a normal life," she says, before laughing. "Yeah, after this you think I'm going to have an ordinary life? But that's really what I want."