So to clarify:
-Entering a fight with the normal 3 enemy boars after your first defeat triggers one-time dialog (but not any of the other mobs, as I assumed the player wouldn't be that far).
-Entering a fight nude in slut mode will trigger a one-time dialog for any of the mobs (and it's unique per mob). This only fires once though, so if you want to see the other mobs reactions you have to reload a save.
-There's no special dialog for clothed, in either slut or normal mode, though the boars will grab you after the first turn with a unique rotating set of remarks in slut mode.
Let me know if any of this doesn't match what you're seeing in the game.