@dokidoki could be her cousin, but honestly, idk if its just me, but looking at all the students i got reminded of all the characters from the original series. like they look like small slightly different versions of our main characters, so i wonder if this is like the oono lookalike or something lol.
I dont really expect to see Oono or haruo for a long time either because its Hidaka's series, and she needs to carry it on her own. since the series started with a wedding, a part of me thinks, we'll get hidaka's wedding to end the series, with both of them being a cameo appearance as their invited to the wedding. hopefully not though, cause id still like to see them a bit sooner and for a bigger appearance