i just didn't take any prisoners in high school rather than actively being callous to anyone - i was generally quite reserved, but also couldn't resist making a good joke or coming after someone if i thought it was funny. if i thought it was funny then, well, good luck! however, that's just my perspective on it, i'm sure somewhere down the line there are a couple of people who saw me as being more than endearingly bitchy and just hurtful. but... that was high school! who dwells on that?