I can imagine Kana in the street having a shock and thinking... "I'm missing something great somewhere!"
I would like to see a work showing us more about her. Why she's with the bullies. And about her finding yuri in the most unsuspecting places. Kana's bizarre yurilicious adventures.
Regarding the useless senpai... I can empathize with her.
And I like how the kouhai took the initiative... because if she had to wait for the senpai to do something, she will die waiting.