Tom definitely sees Harthouse as the cool, popular guy, and so is thrilled when Harthouse wants to chill with him.
Harthouse gets him drunk, gives him a cigar, and then starts to ask him questions about Louisa.
Tom volunteers every piece of information about his sister – pretty much just to look sort of cool in front of this total stranger.
Tom reveals:
that Tom can get away with whatever he wants to because Louisa smoothes it over with Bounderby;
that Louisa dislikes Bounderby, that she married him without feelings and only so that she could be useful to Tom;
that Gradgrind raised his daughter to not have any normal emotions and to just try to be as rational as possible about everything;
that Mrs. Sparsit is jealous of Louisa.
After the conversation, Tom passes out on Harthouse's couch. Harthouse pokes him awake with his boot and then kicks him out.