I used to have nearly every strip memorized. I'm 90% confident that is not a Calvin & Hobbes strip. I have not read all the bonus strips from the large anthol

I used to have nearly every strip memorized. I'm 90% confident that is not a Calvin & Hobbes strip. I have not read all the bonus strips from the large anthologies, nor have I read the strips in the teacher's book Watterson contributed to. So, even if my memory is right, it might be one of those.