There's an episode of The Invisible Man (2005 animated series) entitled "The Last Temptation of Alan", where everyone in the city becomes invisible except Alan Crystal (the main protagonist of the series), being him the only visible man of the city:
https://www.youtube.com/watch?v=MRpKUxWFqRA
Now imagine a The Simpsons version of this, where almost all the people of Springfield turns invisible with a Professor Frink's invention except Homer, being him the only visible man of the town. Marge, Bart, Lisa, Maggie and almost all the people of Springfield would be invisible (except their clothing) but Homer not. It would be a "Treehouse of Horror" segment and its title it wouldn't be "The Last Temptation of Homer" because that episode already exist (Season 5, episode 9) and it has nothing to do with the invisibility. The segment would be called "The Last Visible Man of the Earth" or "The Last Invisible Temptation of Homer", so as not to confuse it with the mentioned season 5 episode. It would be like this fan art:
Someday that will exist. Some... day...