I've drawn late-60s Faustus before but never Rosa! I always daydream about creating a spinoff with these two set in 1969. We'd watch them get swept up in the cultural upheaval of the time, maaaaybe solving some mysteries along the way, more likely just eating a lot of brownies and passing out in a public park.

Rosa gets increasingly into New Age ideology and starts using the word "quantum" at an unprecedented rate in day-to-day conversation. Faustus gets more and more strident with his politics, which for all his ferocity are actually very vague.
There would be a lot of surreal scenes, and it would all be an excuse for me to draw psychedelic backgrounds.

I definitely don't have the time or energy to create this thing, but it's fun to daydream!