because if you try to hook up with the same girl several days in a row and she has like 6 home scenes even without relationship requirement it isn't a guarantee you will be able to see all the scenes.
Actually, as long as you stay ingame the application keeps track of all scenes selected for each girl. If you select the same girl over and over again the scenes already played will be taken from the pool until no scenes matching the parameters are left. Then the tracker gets resetted. This is not saved, mind.
I would suggest making the Flirt button unique for such events. Make it sparkly or something, just to make it stand out. Otherwise most such scenes will never be seen unless you know exactly what you're looking for and when.
See above, I was thinking about a new icon, since the code for that is already there.