the comic is made by mncncr and found at https://twitter.com/mooncancer00

Charlie is the girl with brown hair.
Erin is the girl with blond hair.

I'm probably not gonna keep this updated, so maybe someone else have to take over, when it comes to non-comic extra from this artist
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first and only time we have seen the guy's face so far.

Fairly certain that the netorare tag should be applied to the gender of the character DOING the cheating, in this case (and the case for all of these galleries) male, not female.

Base +6, Bob the janitor +6, ColdHead +6, LunaCat +6, xerorushbluh +6

that is a good point, didn't think about that.
but I don't know how to remove a tag from a gallery

Base +6

I love how in other works, we see Charlie wearing a cat outfit, with a bell collar, and here we see Erin with a dog bone on her collar.
That's cute.

Also, the netorare tag only applies if the man/woman is being "stolen" from the original partner. This, I think, would be "swinging", as Charlie is consenting (more or less) to Erin's involvement with her boyfriend.

Base +9, xerorushbluh +6