Apart from the two of them being desperate enough to try, and sleep with one another to see if that would allow them to get some rest. There were many other factors that they had to consider, and those factors were the things that would be instrumental in making sure that their plan was successful.
And one of those important things was normalcy.
In order to do what they had to do and keep getting away with it, they had to continue acting as though everything was normal, that nothing had changed. And so Derek, when he got home, did not immediately throw himself onto the couch and stare at the door waiting for Emily to ring the doorbell.
