This scene is comedy gold as it's all played on double entendres with Fujiko and Jigen being suspicious of each other.
Mind that both Fujiko and Goemon were invited to what they believed to be a real wedding so much that Fujiko even got Lupin a wedding present! 😂
Goemon decides to leave as well. If Lupin is going to retire there's no reason to stick around.
Jigen follows Fujiko and Goemon outside.
Turns out Jigen is the only one who knew about the heist because Lupin decided not to let Fujiko nor Goemon in! Why not Goemon!!??? Because he cannot lie??? 🙄
Apart form the joke about Fujiko and Jigen being jealous of each other (or jealous for each other?) while it all clearly gets down to the good old "Lupin and Jigen vs Fujiko show" meaning them being wary of Fujiko ruining the heist, it also makes me think, knowing Jigen is after all very kind hearted, if he was sort of concerned about Fujiko being actually hurt by Lupin marrying someone else. Following Fujiko outside to keep an eye on her or maybe even to tell her about the fake marriage, if she hadn't been her usual pissy self.
Story being reprised in episode 6 of part 1 with Fujiko in the role of the bad guy here and Lupin being threatening to her as well. Don’t touch his Jigen ❤️