@yildo I'm pretty sure he would have recognized those. But you reminded me of a new possibility—that he accidentally invoked PlainTalk and brought up one of the PlainTalk avatars: https://www.reddit.com/r/VintageApple/comments/1514st0/anyone_else_remember_the_classic_plaintalk/
I don't remember where on the screen this appeared. I thought it was in one of the menus, like Mr Macintosh was supposed to do, but maybe it was a window…?
Also, did the PlainTalk characters vanish if you didn't interact with them? It's been 30 years, so I don't recall exactly how they worked.