Personally, I wouldn't call Emma selfish. She is in her own way very idealistic: she's very concerned with justice and morality, likes to help people in need, and wants to be a good person. She doesn't think twice about assisting Monika, and she expects the MC and even Kim to actually WANT to help out as well simply because it's the right thing to do.
I would ask you to think back on that story arc and answer this question for me: was it the friend who wanted to track down the blackmailer, or was it instead Emma who had a thirst for vengeance and talked her friend into it to satiate her own selfish need for justice?
I seem to recall Emma's friend saying clearly that she wanted to just drop the case and move on. And she only went to the police once Emma convinced her otherwise. You may interpret this whole series of scenes differently, but if Emma truly was thinking about someone else during this time, she might say things like: "I know you very well, Monika, and you wouldn't be happy if you didn't at least try to track this bastard down." Or even something like: "I don't like letting a person like this run free to harm others, but I'll support whatever decision you make." Those are the kind of statements an unselfish friend would make in that case. However, I don't remember Emma showing any support that didn't involve catching the blackmailer, which shows that her true motivations likely lay elsewhere.
An alternate way to consider this particular story arc is to change the outcome so that they fail to track down the blackmailer. Who do you think would be more furious at this failure: Emma or Monika? And if they failed, do you think it might be possible that Monika would have ended up feeling even
worse about the whole situation when so many people had just wasted their time without accomplishing anything? Especially when she just wanted to move on with her life at the outset? If they didn't get extremely lucky and catch the bastard, I see this selfish manipulation – and that's my own interpretation of Emma's behaviour – of her friend very likely blowing up in Emma's face, because good intentions won't save her when she selfishly runs roughshod over everyone around her to get what
she wants.
This is why I asked if you could point out to me any actions towards the MC that showed Emma acting unselfishly, and why I have to note that you failed to do so in your response. You gave some interpretations of actions she took to potentially help others, but you couldn't find anything that she did to help and support the MC. In contrast, let's consider a few actions by the MC towards Emma:
- MC helps Emma get a new, better job, when he notices that she is unhappy in her current workplace environment
- MC offers unasked-for praise to Emma, and even gives her a shining recommendation to her future boss, by highlighting how much he respects and admires her skills, and how he is certain she will succeed at that new job
- tries on multiple occasions to help her understand and accept her unwanted sexual desires (i.e. the way she gets excited at being treated roughly and like an object by a strong and masculine man), and does not shame her kinks in any way, and only ever talks about them as normal and healthy impulses that she should be able to choose to explore in safe ways if she wants
- helps Emma track down the blackmailer (again, I would say MC is helping Emma more than Monika here, because it is Emma who is the one steering this ship)
There are more, but that list gives you an idea of actions that prove the MC is an unselfish person. He does things for Emma without any need for a reward, or even without the expectation that she'll offer him a simple "thank you". However, I can't think of any corresponding actions by Emma that show similar traits. Even her pattern of word choices make it very clear that she is only concerned about herself (or focused on women by proxy as an extension of herself, when she complains about being forced to suffer "patriarchal oppression" due to the choices of others).
Perhaps Emma was concerned about MC's job in regards to an unethical dalliance Jen, as you say, though that is a bit of a stretch, since she had no way of knowing the two would be in a relationship at that point in the story. But let's say she did, then I would expect phrases like: "You need to worry more about your future, CHARNAME" to be said by her. I can't remember anything like that being offered to the MC. I think I recall her saying she was worried about Jen, but that's it, though I could be misremembering.
Again, I think the dev has created a very interesting and dynamic character with Emma, including a great backstory with MC and the powder keg of emotions and motivations that comprises their relationship. The problem is that she is proving to be too selfish, among other issues, and those are making her into an unlikeable and unattractive LI as the story unfolds. Though that could be intentional for any variety of reasons. The simplest could be: everyone loves a good redemption story. Care is needed though if that's the case, because it's quite common these days that a writer unintentionally makes the character too unlikeable, to the point that they become irredeemable in the eyes of the viewer, and the whole thing falls apart.