When Yuuki Kagurazaka killed Mariabell Rosso and stole her Unique Skill, Greed, it looked like her story had come to an end. Yuuki even evolved Greed into the Ultimate Skill, Mammon, Lord of Greed, making it seem as though he had completely claimed her power.
However, years later, Mariabell unexpectedly returned not as a resurrected human, but as a Manas living inside Yuuki’s own soul.
The reason behind her return was one of the most unusual events in That Time I Got Reincarnated as a Slime, and it began with Masayuki’s Ultimate Skill.
Mariabell Was Not Truly Resurrected
Mariabell did not return because someone revived her from the dead. Instead, Masayuki activated the Banner of the Supreme King, a sub-skill of his Ultimate Skill, True Hero.
This ability recreated legendary companions and heroes as Einherjar, information-based spiritual beings built from their memories, personality, and abilities rather than their original bodies.
When the Banner activated, it recreated a perfect replication of Mariabell, although this replica possessed all of her memories and personality, it was not the original Mariabell who had died years earlier. Instead, it was an information-based copy capable of thinking and acting exactly as she would.
Why Mariabell Appeared Inside Yuuki
Normally, an Einherjar manifested as its own independent being, Mariabell’s case was different because Yuuki had stolen her original skill.
After killing Mariabell, Yuuki obtained Greed, and after his defeat against Guy Crimson, he awakened it into the Ultimate Skill Mammon, Lord of Greed.
Since Mammon evolved directly from Mariabell’s original skill, it still shared the same core authority.
Because of that connection, the replication created by Masayuki’s Banner was naturally drawn toward Yuuki instead of manifesting elsewhere.
Yuuki’s soul and more specifically, Mammon became the point where Mariabell’s information entered the world again.
Mariabell Accidentally Trapped Herself
Mariabell never intended to become part of Yuuki’s skill.
After appearing inside Mammon, she planned to write her own information into the Ultimate Skill simply to torment the man who had murdered her.
She believed she could hide inside the skill, interfere with Yuuki, and eventually leave whenever she wished.
Instead, the exact opposite happened.
Because Mariabell had originally been the owner of Greed, her compatibility with Mammon was extraordinarily high.
The skill accepted her information so completely that she began merging with it instead of merely inhabiting it.
At the same time, the previous consciousness within Mammon had already disappeared, leaving an empty space that allowed her information to take root.
By the time she realized what was happening, it was already too late.
The Birth of Maria
As Mariabell merged with Mammon, she could no longer separate herself from the Ultimate Skill.
The temporary Einherjar created by Masayuki eventually disappeared when the Banner’s effect ended, but the portion that had fused with Mammon remained behind.
That remnant evolved into an entirely new existence: a Manas named Maria.
Although Maria inherited Mariabell’s memories and personality, she gradually developed her own identity.
She eventually viewed Mariabell’s memories as reference data rather than her own life, making her neither the original Mariabell nor a simple copy.
She became a brand-new digital lifeform born from the fusion between Mariabell’s information and the Ultimate Skill Mammon.
Yuuki’s Greatest Prize Became His Greatest Annoyance
The irony was impossible to ignore.
Yuuki believed he had permanently stolen Mariabell’s greatest power, instead, that very power became the reason she returned.
Maria made it her personal mission to inconvenience Yuuki whenever possible. She constantly mocked him, argued with him, and criticized his decisions.
Her greatest source of enjoyment was tormenting the person who had killed Mariabell and claimed her skill.
Ironically, she also needed Yuuki to stay alive, since her existence was tied to Mammon, she frequently helped him during battle whenever his life was in danger.
She protected him not out of loyalty, but because she wanted to continue making his life miserable. This created one of the funniest relationships in the later light novels: Yuuki gained a powerful assistant who also happened to be his eternal tormentor.
Final Thoughts
Mariabell’s return was not a traditional resurrection, instead, it resulted from the interaction between Masayuki’s Banner of the Supreme King.
Yuuki’s stolen Ultimate Skill Mammon, and Mariabell’s overwhelming compatibility with Greed.
What began as a simple attempt to haunt Yuuki ended with Mariabell permanently merging into his Ultimate Skill and evolving into the Manas known as Maria.
In the end, Yuuki did succeed in stealing Mariabell’s power but he also inherited the one person who would never let him forget how he obtained it.
