Denzel is a reaper, once a human who died at age 17. He died of a wound to the  heart, so it doesn't beat - there's a large scar on his chest.
Denzel  used to get on well with his brother and they hung out a lot when Denzel was still young, but when the brother was old enough he left, leaving Denzel to deal with their mother. Denzel didn't understand why, as far as he was concerned they were all happy until that point. This was mainly because his  brother took the brunt of her abuse, which is why he left when he  could, and Denzel quickly realised he was  abandoned and had no one else  to turn to. 

He met Chrono not long after, he gave  him hope. Denzel wore Chrono's ring from then on.
Denzel  grew up like that, getting  critised a lot for not being like his  academic brother (and being blamed for him leaving) and heavy disapproval of his love for music, there was a big argument and all that when Denzel said he wanted to be a musician but he still tried to make the best of everything.
He got  to the finals of a small audition for local performers, smiling and holding his approval letter.  It was late,  but not wanting to go home right away and ruin the happiness he felt, he stalled. It was dark by the time he was walking home, which is when he was shot.

And then he woke up on the  floor of an office off the A106, his heart not beating and his memories gone. Denzel had had such a strong attachment  to the living world, it  made his soul the perfect candidate to become a reaper.

Trivia

• He's left handed.
• He has pierced ears and wears blue studs.
• Blood type: A
• He uses reading glasses. He only needs them for small text or in low light, but only really wears them if he’s been filling out death records for too long.
• He collects sheet music
• His most prized possession is the ring he wears. It was originally  Chrono’s, when they met when Denzel was young. He’s kept and worn it  around his  neck ever since. Any time something bad happened or he was scared, he would wear it.
• His favourite food is Sherbert Saucers
• Has a habit of over-using people's names in coversation.
• Has s habit of humming, tapping his foot, and any visual or vocalisation that shows he's thinking about music
• Will burst into song if he thinks he's alone in the building.