dont think that the game will last that long that we will see Sage leaving College. (if nothing surprising happens to her)Sage is my favorite girl in the game, definitely. I wonder if a happy ending is possible with her, given that this is her last year and then she leaves. Maybe she will stay as a teacher and settle in the same city. For me, there is a lot of passion and uncertainty in a relationship with her, which is why I like them so much.
Overall i would say the whole game will maybe include one whole semester, not much more, at most 1 whole year, but dont think so... its not entirely clear how much time passed until now, but we were traveling from summer to fall, reaching Halloween soon and completed the midterms... so maybe, about... hm 3 months ingame? and i think we reached about the half or 2/3 of the game for now. If there will not be a time-jump ahead, i think the game will end at the end of the semester. And than maybe there are some epilogues reaching a bit ahead in the future.
As for Sage... for me this relationship just didnt work for now... very rocky path. At first she is a slut/bitch, than she uses you as a comfort/rebound guy without any feelings attached (of course the MCs goes along, so "using" is a bit harsh) in ep7 the MC said he dont wanna be the rebound guy... and now he wants to be with her in a serious relationship and Sage agrees... yeah well, jumpy much? I just dont can see that there are really building up deep feelings... and the Threesome with Quinn maybe was hot... but on the feeling-side more a kick in the balls and this whole thing goes more in a direction of an open-unhealthy-relationship like Tommy and Heather.
The relationship with Bella, or especially Jill is much more deeper on the feelings-side.
*edit* and yeah... iam a romantic guy, so what?