80 years have passed since Yuuki's defeat. Rimuru, after dwelling for countless years at the end of time and space, has surpassed Veldanava in terms of strength and is, therefore, the strongest being in the Cardinal world. With his strength, he easily dealt with the aftermath of the final battle and accomplished his dream of coexistence between monsters and humans. Although he is happy with the results, his daily routine consists of constant paperwork. During one of these boring days Ciel, who is worried about the mental state of her master, suggests creating an alternate Timeline and traveling back in time. Rimuru, not wanting to do everything over again, comes back with an alternative idea. Going back in time but with one addition: instead of traveling to his original time of reincarnation as a slime, he decides to go much further in time and become one of the ancient demon lords.

This story depicts an alternate timeline wherein Velzard attends Walpurgis after sensing Veldora's presence. She subsequently meets our protagonist and becomes interested in him after his display at the meeting. After thinking for a bit, she decides to move to Tempest and becomes a close ally of Rimuru. Rimuru and Velzard will sometimes be out of character since it's unavoidable. Our protagonist will be more rational and have an actual spine, while Velzard will not be as cold and ruthless as her canon counterpart. Besides, Velzard is missing a lot of characterization, so I decided to write my own interpretation of her personality based on the original light novel. I recommend at least having seen the second season of the anime since my story will pick up from there. This fanfic will follow the main story beats from the original light novel, meaning some arcs will get glossed over if there are little changes. I'm somewhat OC, so expect a lot of chapter edits or updates because I tend to reread chapters and notice minor mistakes here and there. Also, it goes without saying that I do not own the series 'That Time I Got Reincarnated As A Slime.' Check out and read the original light novel written by Fuse.