"bulk" means more than the native block size, in this case. For example, if you were to just run AES with your key on each block, an attacked could immediately tell whether both blocks were the same, which would be a terrible thing from a cryptographic point of view.
Random-ctr mode consists of picking a random number (N) the same size as a block, and then running THAT through AES with your key to give you something to xor with the first 16 bytes, and then AES(N+1, k) to get something to xor with the second 16 bytes, and so on. (then you transmit N at the start of your message.) Aside from it being a bit tricky to generate 128bit random numbers, it should be TOO hard.