Ichika becomes a bitch corrupted by love and backstabs her sister. Meanwhile instead of making Fuu loves her for who she is, Miku just steps in exactly the same road Fuu tried to get her out at the beginning : muh I'm useless and anyone can do what I can so I will try not to be myself. Cant believe she actually takes Fuu's joke about his ideal woman ( literally Raiha) seriously.
Nino maybe a dick to Fuu at the beginning but at least she admits it and tries to make him fall in love with her for who she is. Sadly it doesnt change the fact that her love for Fuu somewhat originated from her childish dream about a prince riding a horse. You can say that she loves him after seeing him values the sisters relationship more than the exam and his coolness on the motorbike is just the last nail. But even Ichika points out how cheap her love is.
If Yotsuba is truly Kyoto girl who loves Fuu secretly and just wants him to be happy ( like she said in chap 37 he already gave her what she wants aka his smile) and feels like she doesnt deserve him so she shoot herself in the foot, then she kinda deserves him the most. But that's just a speculation and even if it's true, then it will become childhood friend tragedy all over again.
Itsuki, well she's here to eat and win. Her relationship with Fuu is developed quite well and natural with no obvious hints about romantic feeling. Just hope Negi doesnt rely on hack to hand her the W