Generally I only start to pick one person out when they have a personal history of being unfair and shallow. I've talked about her before on this forum, but there is one ENFP girl in my class that i now eat lunch with. She drives me to put her down verbally because, in combination with her original habit of picking on me, she is shallow and she has the same capacity to share as an infant. But, I digress.
The humor that I let others hear is often dull or irony-based, so I usually do not offend anyone. sometimes I get into a groove in the unlikely chance that I find the kind of humor others want to hear. Again, off topic now. I'm being weird today; I usually don't give more information that what is asked for.
To sum it up, no, my humor is not usually hurtful.