Rapacious
1: Given to plunder; taken by force
2: Grasping; Greedy
He knows what he wants and as he presses the Doctor against the prison cell wall, he knows he could take it.
Easily, he could push the Doctor to his knees and take that which he has so long been denied; the Doctor's body.
Hunger and desire course through his veins, yet he stops.
The Doctor must give himself willingly; beg for his Master, just like he used to.
It is a matter of time; waiting until the Doctor is ready to be his once more.
He is not greedy; after all, he already has the Earth...
He will wait.