I seemed to be stuck with Natasha, but just did her second hot tub scene, it is definitely a prerequisite for a lot of her events, it also seems to be the game's intended first sex with her, even though I've already done a before bed sex scene.
Also, it took me way too long to work out that the schedule colours the events red, yellow and green to show their availability status.
Also, it took me way too long to work out that the schedule colours the events red, yellow and green to show their availability status.