HELP???!!!

Ok. So I was watching a Amv and there was this clip of Grell and the Undertaker fighting and Grell dicho somthing like "I didn't want to have to fight you." and then the undertaker dicho "I don't care for laughter anymore." o somthin like that. Does anyone know where this is from?? I'v watched both sesons and I thought I saw all the ovas but maybe I missed one? Did I miss an episode?