Do a day or two of the special K diet and you will be starving by the end of it. My friend and I did it for a couple of days as an experiment and he and I both thought the same thing. We were starving!! I think that is really how the "special K diet" works-- you lose weight by starvation, which is not very healthy.
Now, if you want to maybe eat the cereal for breakfast or even as a snack I see nothing wrong with that. I'd just measure out the serving size (most cereals are half a cup, I have no idea what special K is) and eat that. And I don't like milk as a general rule so I just don't use it-- although you could try soymilk; they have regular, vanilla, and chocolate.
But I wouldn't really recommend the special K diet-- my personal opinion? Its just a gimmick to get people to buy their products.
I'm a burlesque performer and I help to run a nonprofit
Get back into a size 12 (20)
Be able to run/jump again
Improve overall health
Get out of the "Obese" BMI category