In a world where angels and demons are born from human emotions, chaos erupts as a surge of negativity tears open the balance between realms. Sealed away on Earth since she was little, Yuno Grimlock the forbidden daughter of the Grim Reaper was never meant to see the light of day. But when the world began to collapse under waves of supernatural anomalies, Heaven had no choice but to break her seal and send her into battle. 

Years have passed, and figuring out the sources of these anomalies has led nowhere. With her Investiagtion stalled, Yuno power festers, her purpose fades, and the line between savior and curse grows thinner with each day.

Then, without warning, she delivered a letter from the one person she wanted to hear from the most.

“Yuno Grimlock… it’s time to come home.” 

Yuno Grimlock is the forbidden daughter of the Grim Reaper. Her mother, a human, gave birth to her in hiding, away from Heaven’s watchful eyes. But after her mother’s mysterious death, Yuno’s identity was discovered, and she was sealed away in the church under constant surveillance. 

To bear a child with an angel is a sin under normal circumstances, Heaven would have executed her but Yuno was special. The Seraphium known as Birdman allowed her to live, on 2 conditions.  Remain cut off from both Heaven and Earth and train her emotional abilities to become Heaven’s weapon. 

In the church, Yuno lived under the eyes of angels and the church members. She was raised by the homunculi Katsuki, Megumi, and Momo all experiments of the infamous angel Asbeel. There she was isolated, constantly asking the church about her father and praying for a chance to see him again. Cut off from the outside world, she spent her time watching television and reading books, slowly developing a fascination with humans.

Angels occasionally visited to check if she had developed her powers. As an angel-human hybrid, Yuno was expected to generate strong emotional energies but to their surprise, she could not access them. Despite training, her abilities never awakened, leaving her insecure and frustrated.

During one visit, she met Takashi and learned that her father had taken on an apprentice. Though jealous and hurt that her father had another child, she tried to befriend the boy but he ultimately rejected her.

Yuno remained sealed until the age of 17, when Birdman returned to the church with an offer: dedicate yourself entirely to finding the man who disrupted the worldline, and you will see your father again. With that, Yuno’s journey began, and she has since scoured every corner of Keinan City in search of the truth.

Takashi is Lord Grim’s special reaper-in-training, sent to Earth to assist with the ongoing investigation affecting the world line. He partners with Yuno Grimlock under the guise of a fake engagement. Quiet and reserved, he often keeps to himself, and many are intimidated by his cold, ominous aura.

His origins are shrouded in mystery, leaving many to wonder why Lord Grim would even take on an apprentice. Despite this, Takashi is an exceptional Grim Reaper, excelling among his peers. In his first years as a Reaper, he passed on over a million souls, earning him top-ranking status. He wields the powerful ability of Acceptance, one of the strongest among Content angels, which allows him to halt emotional dysregulation and place spirits and humans in a state of detachment.

Takashi wields a twin scythe with both offense and defense modes, capable of effortlessly cutting through opponents. It is primarily used to combat Demons and revenants. Many reapers look up to him, though he never acknowledges it. Surprisingly, he also maintains connections on Earth, which catches Yuno off guard, as she assumes he is a loner. He is extremely dedicated to his work, often disappearing for days while tracking his targets.

Cracks in his stoic demeanor appear in mundane situations like entertainment and food; he gets excited over meals, watches movies and enjoys playing video games during his downtime. He's also addicted to coffee. Overall it's seems he lack empathy; he performs his duties without concern for morals and will kill if necessary to complete his mission. This controversial approach often clashes with Yuno’s ability to understand and navigate human emotions, creating tension between their contrasting moral perspectives. He also seem to forget he met Yuno as a kid.

Katsuki is Yuno’s guardian cat and a fiend created by the former angel Asbeel. He is a human soul stuck in a cat's body. He came with Yuno to the mortal realm 5 years ago and has been ordered to watch over her by her father ever since.