I actually like these two, I agree that the "big reveal" wasn't anything transcendental, I thought it was going to be something related to her family... But basically, Chika just doesn't have enough confidence in herself so she's afraid of changing and to love someone else is harder if you don't love yourself enough, you become negative and reject of your own happiness ... But at the end of day, it is real love, so she couldn't bear to lose her either, so I think they'll be fine, I really love Chika.
And sex is good no matter what they say