((I'm on my tablet, Woyo, whatever's in the spoiler will have to wait because they don't open on here. Sorry!))
The TARDIS soul stayed within Mari, its sadness touching both her and the Doctor. He tries to push it away, tries to ignore it.
All this time and still you refuse to listen to me? she seemed to say. Why do you even bother? You know I'm right. Her melancholy started to penetrate the Doctor's heart, and his anger and frustration became an equal level of sorrow.
"Mari," he said after a moment, "I'd really be much happier if you stayed."