I think everyone can be lazy at the end of the work day, this is absolutely usual thing)
And Celestia also would like to watch her favorite serial even if it is too late, cuz why not.

But "the night is dark and full of terrors" as it saying
She had to know that night - is time of night princess, so... =3

Just decided to color my old sketch)
I really love a theme of two princess, this always make me smile)