I appear to have missed something. On the stat screen, slots 2,5,9,14,19 and 20 are girls I still haven't met. From other comments, I assume 2 is Aoi, and 5 is Fumari.
On the map, I have not unlocked the fourth location outside the house.
13 of the other 15 girls show as done for the current update. Ai's hint is "Something must happen"; Otome's is that I need to meet and progress with a number of girls outside the house. As noted above, all the other girls I have met are finished for now (including Kaori and Yuri; Meiya; Sanae (who is actually in the house with Ayase), and the gym and library instructors).
My understanding was that I meet Aoi at the "corner" Street at night (I'm assuming that's fourth row, first location on the map). I've just played through a full week, working at the store each evening; I end up at that location when night starts, but them am immediately moved to my room.
Sunday events: just caught the mouse (grammar note: one is a mouse, two or more are mice).
My current hint says I need to progress with Otome.
I did take the girls to the beach once.
Can someone tell me what I'm missing? Did I mess up the ability to meet other girls by doing something earlier?