Hmm. Which 'friend' do you mean? That could be the orange-haired one, could be earring girl, could be flashback weed-smoker guy, could be ... certainly not speedrun boy. Not sure.
Master energy aligner does good whilst having selfish intent, but does introspection and recognises they have selfish intent, whilst trying their best to avert course. They are not villainous. Speedrun boy is clearly a true villain for writing shonen manga, but is otherwise a good lad. Rothschild weed boy seems like one who is too young and too wealthy to comprehend the consequences for their actions, thus they're destructive but I don't think they're villainous. Earring girl however is villainous. Going after a friend you betrayed to disentangle all of their meaningful relations just to alleviate the guilt of your betrayal is something they'd monologue about in a Hellraiser film
Hmm, I see where you're coming from. I do think somewhat otherwise though; the 'betrayal' is obviously far more personal to Amber than it is for Freya, who endured Amber treating her as a venting machine for something like 5 years before getting weary of it and doing some venting of her own ... which did happen to spread because gossip is an awful phenomenon. Not to say that it wasn't a shite thing to do, but it is understandable, since their friendship wasn't a healthy one.
Nor is she really all that great of a friend to Amber for falling back on their shared history in order to fuck with Daisy when she was the one who wanted to disregard that in the first place, but the scene that convinced me that while she may be somewhat of a shitty person she isn't an outright villain was when
Daisy and her are talking at her place just before they discover Amber hit her head on the sink, and she says something to the effect of 'that whole I hate myself rant? I had to hear that every friday for the past 5 years'. Just her dialogue in that scene really - before she did come off as somewhat of a selfish bitch, but that bit of talking made it seem to me as if she's Daisy's opposite in terms of their relationship to Amber - Daisy's intentions are selfish but her actions are selfless, and Freya's intentions are relatively selfless but her actions are selfish as hell.
Course this is all relative, what with it being character interpretation. Could go any which way with how the plot develops later on.