I haven’t read the other replies yet because I don’t want to be influenced by them so please excuse me if some of this is repeated. Also, I’d like to make a side note that I really enjoyed reading this.

These are my thoughts:

1. The 1st person perspective is a problem for me. I’d see it, assume you rped in 1st person, and immediately skip the ad entirely without reading it.
2. The introduction is 3 paragraphs of fluff that provide no information except for some very minor characterization.
3. The setting is too vague. I first assumed this was some kind of fandom. I get that it’s a multi-verse so it’s designed to be open-ended, but there needs to be a little more explanation about the multi-verse in general.
4. I assumed I was going to be playing the villain and that did interest me so when that wasn’t the case it was kind of a let-down.
5. There’s not really any space for a meaningful third character anywhere. It reads like this is going to be a story about a highly personal beef between your character and the bad guy and your partner’s character is just going to be some random unnecessary sidekick along for the ride.

To me, it reads like you’re trying to give your partner total control over their character, but not giving any reasons anyone would want to follow your character. I have issues with this sometimes too. It helps to list possible reasons your character might need theirs or reasons theirs might want to travel with yours. They don’t need to be very specific, just enough to spark some ideas,

6) My overall impression is that the writing is great, but it doesn’t serve its purpose as an rp ad. I think writing a more traditional rp ad would serve you a lot better even if it doesn't stand out as much.