Post movie. Credence moves in with Graves. Credence is poking around (maybe tidying up because he feels like he has to) and finds some sex toys (hand wave historical accuracy if needed but I guess dildos have been around forever and apparently butt plugs long enough too but IDK - or maybe they're magical ones) and asks what they are.

I'd love if Percival is embarrassed to start and very awkward about explaining. I don't care what happens in between or how long it takes but would love it to end with a practical demonstration (on a shy but enthusiastic Credence preferably).