A significant branch.

I clear my throat, "So, I wanted to talk about obviously the kind of dirty talk Trev tried... the more cucky stuff."

"And then the other major part of it which I guess could be related as well? But how would you feel about me doing what you're doing? Y'know, going around and sleeping with other people aswell? I guess, what I'm saying is that I want to take a more [TBD] role in the relationship... How do you feel about it?"

Vi puts her hand on her chin as she thinks.

This is the end of the introduction arc and now it'll start to branch somewhat... There will be (for now) two main branches

A submissive branch that will involve Vi being sluttier and informing Erik after the fact, more dirty talk that humiliates Erik and 'cheating' role play, more dominant, and just generally Vi leading the relationship a bit more, there will still be light swinging in favour of Erik but significantly less.
More "ask for forgiveness rather than permission." "Implicit consent"

The dominant path will involve, obviously Erik taking the lead, there will be no dirty talk that humiliates Erik, more swinging in Erik's favour, and maybe some humiliation and cucking of Vi instead of the other way around.
More "Ask for permission rather than forgiveness." "Explicit consent"

Both branches will involve Vi sleeping around, but will just change how Vi, Erik and others react to the sharing.

I'll probably work on whichever path I can think of stuff for more in the moment but I'll generally try and keep it even. Both branches will have pretty similar arcs, so characters and situations will mostly be similar.

There will be no hard 'NTR', No one will steal Vi away, there will be moments of reassurance and re commitment several times through the branches, there will be very kinky role play,

BUT I will not write Vi being taken away.