Finn keeps seeing this ghostly bald dude in Jedi robes hanging around, and then decides to try and talk to him. Turns out it's the Jedi master Mace Windu and also Finn's grandfather/granduncle. When Finn opens up to Windu about his time as a Stormtrooper Windu performs and acrobatic Jedi flip off the handle and gets super protective of Finn even though he's a ghost and can't do much.
+100 for Windu teaching him lightsaber basics, he may not be force sensitive enough to qualify as a Jedi (thanks to the goddamn First motherfucking Order, his words) but he'd be damned if his grandson/grandnephew can't use a lightsaber properly +100000 The afterlife has eased up Windu's sense of the whole Jedi code, offers romance advice for Finn's obvious crushes (Poe and/or Rey, I ain't picky) +everything I own for Pulp Fiction-esque curses when Windu gets pissed.
gen - Finn is related to Mace Windu, Windu guides him as a Force Ghost
+100 for Windu teaching him lightsaber basics, he may not be force sensitive enough to qualify as a Jedi (thanks to the goddamn First motherfucking Order, his words) but he'd be damned if his grandson/grandnephew can't use a lightsaber properly
+100000 The afterlife has eased up Windu's sense of the whole Jedi code, offers romance advice for Finn's obvious crushes (Poe and/or Rey, I ain't picky)
+everything I own for Pulp Fiction-esque curses when Windu gets pissed.