Looks like Koakuma speaking, so "witch" may be a typo for "demon".
Nah, I'm pretty sure it's Patchy talking. If you look down, you can see Patchy is holding Koa, so the top panel would be Patchy still, since you can see she's holding onto Koa there as well.
I've had just about enough of you human creatures.... Since you're so foolish, at least remember your scriptures and teachings:That's right, I'm a witch! I don't care about that! Call me that if you want!! Patchouli speakingBLAMOh, dear.If being one of you means being infected with such ugliness, then I'd rather be called a demon!!ShudderROOORRR