@basiceden She is aware of that, but you see, those who wear thier motives on thier sleaves are easier to deal with than those who dont. She knows her class is special and being given a commander position she can move up the ranks in a top clan. She doesnt owe anything to them and can operate logically on give or take. And there is the posibility of going back to earth too.
The MC didnt even lie about his motives, he simply kept to himself. Which brings the question of for what purpose is he doing what he is doing? And considering his confidence, there is a possibility that the mcs life was never at risk but he was simply playing out scenarios to deceive them into thinking so.
But worst of all, he didnt even ask! You say throw away good will but she didnt betray them. And she was even willing to open spots for all of them. MC said no, and said he might make his guild but didnt even try inviting her. Is she suppose to beg the MC to let her in?
She doesnt even know what his motive is, maybe he doesnt want to go back to earth and wants of rule as an emperor. Then thier goals doesnt align and she would be fighting against the top clans dor things she doesnt even care about.
Sorry, the MC is the one at fault here. He should have just told her that sure I can do more but i dont want you guys to over rely on me cause i cant always be there. so i am helping you grow. He doesnt need to tell them everything, just enough to show they are comrades and they do mean something to him. That he needs them.
But MC didnt even bother asking her, so she took it as he didnt need her.
I think you are to used to mnga where harem members blindly throw everything away and follow the mc without any questions asked. Her behaviour is normal for anyone with a head on thier sholders.