Cast: Nagisa Shion- a 16-year-old boy, diagnosed with leukemia at age 5. He's spent a majority of his years in the hospital. His parents never come to visit him, but he believes they are working hard to pay his hospital bills. During his 16th year, he meets a volunteer who helps raise money for cancer patients. His strength is his calm, straightforward attitude. His weakness is spiders and not being loved by those he cares about. Nagisa's hobby is collecting manga and butterfly images. He's never gone to school, but studies as much as can during parts of the day.

Aaron Komiya- an 18-year-old volunteer for cancer drives and a survivor of cancer. He works part time at Nagisa's hospital, walking cancer patients out to the garden or into town. He's mainly assigned to Nagisa. He stays by Nagisa, an unbreakable, but unbearable love forming between the two. Aaron's strength is his ability to stay calm and react quickly in an emergency. His weakness is blood and seeing someone's insides. Aaron's hobby is puzzles and video games. Helping out at Nagisa's hospital is part of the college requirements for become a doctor. He aims to work full time where Nagisa is once he graduates. 

Lee- a 17-year-old boy in the same room as Nagisa. He was involved in a multiple car pileup, being the only survivor with severe injuries. He's got a cold attitude but acts as Nagisa's stress reliever. Nagisa accompanies him to his physical therapy sessions to cheer him and other therapy patients on with confidently filled words. His strength is Nagisa and his ability to push forward during tough times. His weakness is sudden cute moments and his willingness to do anything for the one he loves. Lee's hobby is running and sketching. His grades are flawless, and he's the star runner of his school. His injuries may prevent him from ever running again.

Proof of Life is about three young boys, all facing their own real life challenges. One boy has death knocking at his door but channels all his strength into others around him. The second struggles with his feelings for his charge and his duty as a volunteer caretaker. The third pushes through his painful recovery while swallowing his love for his roommate, remaining as a stress reliever. Their lives intertwine and interfere with each other. But, when death comes calling for one, will the remaining two put aside their differences, their feelings, and their own problems, to guide him back to the world of the living? The story focuses on the struggles of all three boys, along with their love, hate, sadness, and their will to push forward by pulling each other down the paths of the past, present, and future. It's a story of happiness, sadness, love, hate, strengths, weaknesses, fear, courage, and one's true feelings on the matters at hand. Will romance bloom, or will death prevail, ruining everything that's been accomplished? The only ones who can change their fate are themselves, and the people who surround them. Enemy or ally, friends or family, or the very doctors aiming to save the lives of their patients.