Lol. Yeah, Rikugo seems to like randomly inserting Nakazawa into their stories.
What I'm really curious about is that this isn't the first time I've seen some kind of gag "pairing" Nakazawa and Ms. Saotome together. One example I can think of is in the fan animation "Great Detective Homura-chan", where she's 'seducing' him in the background in one scene (https://www.youtube.com/watch?v=GBLUdFvF8Jw).
I love Rikugo's Doujinshis so much. Boy, if Junko was a magical girl when she was young, and turned into a witch at one time, she would probably be intimidating Homura with her witch form's glare. Sayaka, Homura and Madoka's interactions were golden. The Homurella part was probably my favorite.