Thanks, yeah I realized that I didn't go to Tech Wizard's Lab the first time. Went on a date with Devya instead. Went ahead and replayed from the beginning and went to the Lab this time to start dating Nightingale, so now I get that extra date.
I don't remember her saying she would replace Lotus (or I might of just not remembered that part), but I understand her saying Emma should date Nightingale. Emma's powers are unknown and need testing, and as a Doctor, they want to fully examine how they work. Yeah Emma already got Meg's power permanently, but she wasn't there for that. So makes sense that she would want to see it for herself to see how your body changes to getting a new permanent power. Nightingale just seemed to be the obvious candidate since she already works with Tech Wizard and can help with results.
And on the plus side, maybe after it's all over and you end up getting Nightingale's power, they might find out how it triggers and find a new way for you to permanently gain someone's power. This way you don't have to wine and dine every single person just to get a new power lol (and you don't have to break everyone's heart once you get their power and move onto the next person in line).