Subtracting a negative integer is the same as adding a positive integer. Adding a positive integer to any number always makes the answer larger than the original number. Therefore, if you subtract one negative integer from another your answer will be always be *greater* than the integer you started with.
Example: If you start with -8 and subtract -3, the answer is -8 - (-3) = -8 + 3 = -5.
-5 is greater than -8.