Please remember the main plot was Mimiru being insecure as a gyaru, thinking it was wrong for her to be a otaku and felt like she was just cosplaying. Her feeling accepted by her friends for who she is, and getting closer to Yuuhi is what she always wanted.
yea that is what the plot was about, but the girls' love tag is literally RIGHT THERE, so it's not exactly surprising that people were expecting SOME sort of relationship to come out of this, especially with the amount of teasing and tension building between the two of them