Glad you've enjoyed it! <3 in case you weren't aware, you can keep playing once you reach day 80, the game prompts you to set the clock back two weeks but you don't lose any progress. Since the full day expansion is still a long way off, there's not really any downside to using it!
You can already go on dates with Scarlett! You need to be her girlfriend, then go see her in her room. At the moment the dates are extremely short little scenes, only a couple of lines and pics, but I may expand them at some point.
Harem/polyamory is planned as an ending, but the closest we'll have before that is all the parties and side events that involve group stuff.
Thanks for playing! <3