Montparnasse and Éponine have something going on, though it’s not clear what.
Montparnasse escaped capture after the attempted robbery because he left early, “more in a mood to amuse himself with the daughter than play hired assassin for the father.” In a later chapter, he’s described as “perhaps [Thénardier’s] unofficial son-in-law.”
It’s not clear how far it goes, though he’s more interested than she is. (She clearly has a thing for Marius from the moment you first meet her as a teenager.) In any case, it’s odd that Hugo dances around this, considering how frank he is about, for instance, Fantine’s relationship with Tholomyes.
Mostly in
https://hyperborea.org/les-mis/book/lark/
On Tumblr (Re-Reading Les Mis)