To unlock Mikasa and Nobara, you must follow the Slave route for Ash.
To get the event with Asuna and Lucy, you must complete their stories in the talks and come to the Living Room in the Waifu House in the morning.
So is it Asuna/Lucy (Ash's Love) or Mikasa/Nobara? (Ash's Slave) Is there no way to have all four?
That must mean I did everything I could in this playthrough. I'll make a new one.
Yes, it's impossible to have all four at the same time.
