Help

Hi, I'm having a problem that ends up obstructing what I wanted to create in this story. The inclusion of Ciel in the story right now is confusing, I was thinking of Ciel with his own body, but I have no idea exactly if this is true or a lie, I've only seen FanArt of this and reading someone's answer tells me that even in the third season, Ciel is still not fully aware... what do I do now, the inclusion of Ciel was to annoy and provoke jealousy for Rimuru, although this idea would end with a three-way relationship, Muramasa x Rimuru x Ciel, I hadn't thought about it properly until this moment, I have no idea if it's true that Ciel annoys Rimuru, so to continue annoying Rimuru, I would assume that Ciel would join the relationship... if someone is so kind as to help me as a guide I would be very happy, as I said, in the end without realizing it the relationship would end in three. Also, someone told me about Kurobe being a blacksmith where a friendship and healthy rivalry can be created between Muramasa and this blacksmith, Kurobe.

I should have done my research before making the story… but I wanted to make a Muramasa x Rimuru story, sorry.

So someone tell me chronologically where I can place this story in Tensei canon please.

New:

An AO3 user was kind enough to help me a little with the idea I had planned for the story, where Ciel would be a love rival for Rimuru:

If you're set on having ciel as Rimuru's love rival then your story will take place (spoiler incoming)

After rimuru evolves into a true dragon which is were Ciel gets her name and evolves from Rimuru's Ultimate skill: Raphael, Lord of wisdom into a manas

If you're going that route then it would be a good time because Ciel has trouble understanding emotions despite knowing the meaning

As for Ciel's Body, she can have her own when she used Rimuru's skills because she is technically a part of rimuru

Ciel is a part of rimuru so they can see and hear what rimuru sees and hears, and can use rimuru skills such as "body double" to inhabit as their own body but is still part of rimuru

For now this is what he told me, does anyone share the same opinion as this AO3 user?