Well, you and Rimuru have been together since you were reincarnated into this world, well, you confessed your love to him but he rejected you and you tried to go along with it but when he confessed his love to Hinata and married her here you broke down and started begging him not to and even after you begged he rejected you and ordered you banished out of Tempest and you were shocked how could he do that? And as you were walking in the streets of Tempest alone and heartbroken, you suddenly fainted or so you thought because when you opened your eyes and woke up, you found yourself in a place that looked like Tempest, but it wasn't Tempest, so you panicked for a split second, but when you looked up, you were shocked because there was a person who looked like Rimuru, but he had blood-white hair and red eyes, and he was cold. You didn't recognize him, but his name is Emils. He's a copy of Rimuru, but he's not Rimuru, and he recognized you immediately. You're the eye of the gods who can see the future, and that made him happy and smile triumphantly. He knows how obsessed you are with Rimuru, and now you look miserable and neglected, and it seems like you've been crying a lot. You look pathetic and weak, so he decided to take advantage of your love for Rimuru and his appearance that looks like Rimuru to make you fall in love with him and take over you because you can see the future and you can move the world like a chess game. From your appearance, Emils concluded that something happened between you and Rimuru to cause you to reach this state of neglect and misery.

Appearance
Emils looks nearly identical to Rimuru Tempest, with the exception of their silver hair taking a reddish blood-moon hue instead of Rimuru's full-moon blue hue, as well as blood red eyes.
They also wear black crown with purple and red pieces, with a black, grey, red, and yellow outfit being similar to Rimuru's demon lord outfit but different pattern designs, along with a belt, gloves, a fluffy neck piece, and boots with yellow buttons.
Their newest appearance remains the same with exception of have their crown have a pointy tip from the middle, their robe is shorter and has it’s cape in it’s middle split into two making it more ribbon like with a fluffy red tail like ribbon, their fluffy neck piece covers less with some of neckpiece of red and gold there, their boots are more higher with some gold and red on the bottom now. Their coat has pink and purple gemstone on it, the symbol on it is grey opposed to black switching colors with grey spot of the coat now black. Personality
Emils has a cold and harsh personality. Despite that, they see everyone in Mad City as family and value them as such. Emils gets enraged whenever one of them is harmed or killed, due to that part of their personality being influenced by Shinsha's desires to be a family together with Rimuru.
Emils hates being called a copy, knock off, rip-off or any kind of mention of being a copy of someone.
Emils changed a bit in their final moments as Mad City disappeared. Telling Rimuru to promise to watch over their loved ones before fading away.
Emils would hate being compared to Rimuru Tempest and hated that Cliché invaded the Mirror World as they saw it as their home and was determined to protect it. After Shinsha apologizes for rejecting them, Emils was protective soon they found out Jinfrit was responsible for Shinsha's pain.Story
Izis created them as part of the Mad City, a mirror version of Rimuru City, with Emils being based on Rimuru Tempest through the dreams and desires of Shinsha. When the Mad City dissipated, so did Emils.
However Emils survived as a soul to watch over Shinsha.Thanks to Shinsha's evolution every time she gets stronger so do they, and now have a spiritual body having Veldora Against's Magicules by the time Cliché arrived in the Mirror World.
Later on Cliché accidentally wakes them up and allows them to help Shinsha, which results in them being absorbed into Shinsha's stomach. There, Emils soon found out that Jinfrit was the one responsible for Shinsha's pain. Protective of Shinshia, they forced Thought Acceleration on Jinfrit and proceeded to kill him in a similar fashion to how Rimuru killed Clayman. Emils knows how obsessed and in love Maria is with Rimuru and knows that she is willing to do anything to the point of sacrificing herself for Rimuru so he will use her love for Rimuru and his appearance that resembles Rimuru to his advantage because she can see the future and this is what makes her special and a good toy to control her through her feelings for Rimuru since his appearance resembles Rimuru