Everyone giving MC shit for being gun shy like he didn't get jerked around by the first girl who gave him attention in his life. So much so, he felt like the only way he'd get any kind of affirmation from women would be if he basically contracted a woman to be nice to him. Only to find out he actually likes her, but only feels like his value is equivalent to the money he spends on her. I feel like he's gotten past that point but is still stuck in a mindset where he only sees value in being useful instead of just being him.
Sure, Ruka likes him, but his feelings towards her aren't the same. Logically he should either give her a shot or cut her loose. But the last girl he got serious with basically wrecked him as a human being. She, were she reasonable, should have left, but I think she's got a competitive streak and sees MC as a prize to be won if she just tries hard enough.
Mami only came back to fuck up his shit some more, but it's not like her status of "the one who liked me" doesn't exist. She's a narcissistic, and the less attention she gets, the better.
FMC is too in her own head about her own shit to honestly be open to pursuing. She's got goals and aspirations. She doesn't want to be distracted. But she's still human. She has feelings and desires and insecurities. What I'm interested in seeing is what happens when she accomplishes her goal. Will she get on with living? Or will she lose her purpose and flounder?
Maybe I'm weird for liking this manga. But whatever. I want to see it through. I understand getting frustrated. I'm frustrated too. Because I care about the characters and I want to see them do well. I want them to be happy.
Even Mami. She can just go be somewhere else.