It's interesting how this webcomic has been going for so long that conceptually the idea of a "Hipster Girl" just doesn't really exist anymore. Like this series is such a time capsule of early 2010s culture, it is really something that couldn't have been made outside of the era where gaming sites like Screw Attack or animation channels like MondoMedia existed but it just persisted into the modern era like a cave man frozen in ice. Like It wasn't really unique for it's time, there were many webcomics about 20 somethings revolving around their lives and situational humor that would be fairly topical for a person in their 20s who regularly used the internet but it is rare for such a comic to still exist and have not just become one with nothingness and ceased to exist or try to reinvent itself like it's contemporaries. It is like a pristine undisturbed grove that stands there unfazed by the passage of time.
Honestly if anyone could make a throuple work it's these 3. Yeah Sophie can be a bit selfish at times but she's honestly grown alot since the old "comic strip" days, and I'm pretty sure Erika wouldn't change at all even if Sophie & Arthur started dating since she genuinely cares about both of them.