Asks a question

She's looking at a decaying building and asks

Sammy : "What can we change in here?"

Cerve : "What do you have in mind sweety?"

Sammy thinks for a moment.

Sammy : "Can you turn that building into this house?"

Cerve : "Yeah that should be possible"

You're interested to see where she's going with this. And before your eyes a fog rolls in front of the building, growing denser until the building is entirely obscured and then all at once dissipates revealing an anachronistic rendering of your perfectly intact house among the ruins of an abandoned cityscape.

Sammy : "Come on"

You follow her in. Once inside the door closes behind you, as it would in the real world. Without the ruins for context this suddenly felt a little too real. If you went to sleep in this simulation and woke how would you tell you weren't in the real world? The idea makes your skin crawl.