I pissed in my prother's coffee cup

last night my brother asked me to get him  some decent coffee from StarBucks in my way home, I did, but while i was in my way, nature called, and i was angry too, so i stopped to take a leak, and while i was drawing a map on the wall in nearby alley using my piss, the idea of peeing in his coffee came out of my sick mind, cause i was holding my dick with my right hand and the coffee cup with my other hand, so I "dropped" little piss in his cup to my surprise, the whole thing felt so funny when i reached home and gave him the coffee cup, he started drinking it without noticing anything i was happy i took some revenge   :)