SB is a 63/0 player. Passive postflop and calling too much. 
MP is 70/48 over only 23 hands. He has shown aggression postflop but I couldn't see his hand in those situations.

Preflop I hope is fine vs such a loose range, deep IP with decent KK.

Flop: On the one hand this flop is pretty good for me. Not great, but hey, oesd+bdfd+OP. On the one hand I feel like I have to bet that flop since it is one of the better ones for my hand + there is sooo much to protect from.
On the other hand I'd hate to face a shove. If SB x/shoves I certainly would have to fold since he is passive and therefore I will face very strong hands. So b/f against him would hurt, but not extremly much. Additionally it won't happen that often (comparing the wideness of his preflop cc-range to his x/raising range 150bb deep).
I'd feel bad to fold vs a x/r from MP, tho. Getting it in with an SPR of 5,5 here seems very amibitous, too. Especially since I don't have a big sample or any certain reads I might make a huge mistake (in case he just ran hot for 23 hands).

In this hand I decided to bet (1) to protect and (2) since I felt like x/raising ranges here with deep stacks will be very strong and I can fold. Like/dislike? Sizing?

Thanks!