Well.... after some re-readings, somehow I came to the following conclusion:
The "girl kiss" the beginning is the waitress. Apparently, that first kiss was a kind of "test" for his part, years ago, after which she concluded that she prefer the boys (or be with a girl was something that she couldn't face at that time) and left our MC lez-made but with no-girlfriend.
Our MC develop some kind of trauma: the girl she liked was "discovered" by someone else and was taken from her, so when she meets "the new girl" and feels somehow attracted to her, she can't help but remember the previous experience and think "Maybe if she is so simple, with such low self-esteem, nobody will discovers she" (AKA, nobody will take she from me).
Suddenly (and, in my opinion, without any reasonable justification to return to the history), our "first kiss girl" reappears (the waitress) and for some reason also unjustified and absolutely out of the blue, she kisses again our MC just before going home like nothing.
Since the black-haired girl has some feelings for our MC (as all we could perceive from minute one), this sudden kiss provokes to her a certain jealousy, which leads to our MC to, also, Pseudo-conffess herself...
Assuming reasonable this "conclusion", the attempt of argument doesn't seem bad to me, but the narrative leaves much to be desired. What a shame...
last edited at Jun 3, 2016 7:30PM