I am pretty sure there's a rule about this but as I understand it: the defense works at its pre-drain amount against the attack. So:
Drain rolls 9 points, power defense is 5, net result 4 CP drained (2 points of power defense drained, since adjustment attacks against defenses are halved). Next time, the drain rolls 5 points, going against the Power Defense of now 3. 2 points get through, draining 1 more Power Defense, and so on.
Not ashamed of my vote: I have never liked using photos of real people. I am imagining a world that looks a certain way- let's say comic books, with latern-jawed heroes with their mighty seven-heads proportions-!
I do _not_ want to pop open Iron Man's helmet and go "Holy Hell! That's Dennis Franz!"
More subtley: I find the use of photos of real people and places (with the wxceprion of fantastic landscapes) to be extremely off-putting and it does hard damage to my suspension of disbelief-- and I am typically the GM! It is like the _one_ thing that I just can't roll with. I also accept that I am probably the only person on the planet for whom this is as big a deal as it is, and it stem,from the fact that I am an old fossil who has been gaming since before we could screenshot someone from the internet so art feels more "right" in the context. Alternatively, it could be that I do not want that exact and detailed a face or body type; I have no idea.
If you can't draw- I know I can't- and dont know anyone who will whip something up for you- screenshot a drawing off the 'net and show that to me. Give me a stick figure done in crayon. _Describe_ the character to me and I will block in a 2e character mannequin (badly) for you!
Just do not give me an actual photo of an actual person or an actual animal,or an actual car.....