She who Dances in Dreams is a mission similar to Episode 5 of the video game, meaning that you wont be able to find Scarlett while playing it.
Furthermore, Killer is Dead Episode 8 depicts Mondos dreams, and his childhood.
When the mission starts you can notice that even the environment is similar to the one featured in She who Eats Dreams.
When the mission starts, move forward and follow the path in front of you, killing all Wires that spawn along the way. At the end of the path go through the door that leads you to a mansion and kill more Wires.
Continue to move through the house, following the main corridor, and then the door on the right side, which eventually will take you back outside. On the island, fight your way forward, and go left. Cross the inner courtyard of the Japanese pagoda, but stay alert because more Wires will spawn.
Once you exit the said pagoda you will return outside, and you have to push forward following the only path available. Eventually, you will trigger a new cutscene showing Mondos mom inside the kitchen. During the cutscene, you will see David knocking at the door.
Even if Mondo tries to stop him, David kills Mondos mother, and to continue you will have to complete a mini-game.
The goal of the mini-game in Killer is Dead Episode 8, is to make sure that Mondo only strike David or his enemies.
Target them using the left thumbstick, and then press the attack button; but make sure you dont hit young Mondo wearing the white shirt.
When the health bar at the bottom of the screen empties, you will trigger another cutscene showing David who cuts Mondos arm.
Continue to watch the events depicted in the final cutscene, as they will explain how Mondo was saved and brought to Bryan.
At the end of the cutscene you will complete Episode 8, unlocking the achievement/trophy named In Your Dreams, and Episode 9.