Moving around often because of her father's job, third grade student Hitomi Kurio has always struggled with making friends. Alone and neglected, she dreams of owning a dog, but knows that her family's ever-changing location would be a detriment to the wellbeing of one. When Hitomi learns about the "Happy Walkers" program that allows loving families to raise potential guide dogs for a year, she yearns to become a trainer.

Three months after intensively studying dog care, Hitomi gets accepted into the program and meets her new four-legged companion, whom she calls "Eye"—a name derived from the Japanese word for "love." Though he is timid and weak, Hitomi vows to make Eye the best guide dog in the whole world. Hitomi raises Eye with love and they form a deep relationship, but she has to let go when he is ready to work as a proper guide dog.