Wow, that was fucked up.
I also went back to reread chapter 1 and I don't know, what you guys are talking about. That shit hat went all over MC. Laughing about how he has lost all his HP (due to the cursed item) and how his way of life has ended/hit rock bottom. That was our first impression of him and it was baaad. No matter how you twist and turn it, (him being disappointed, trying to challenge him to do better or putting him off out of harms way...,) that guy just had a bit too much fun taking a shit on him.
Nope, that asshole Dario and the Dario, we are presented with now, do not add up. I get, why the people hate him and yeah...he was kind of the prototype of that douche in the former MC's party, in stories in which the MC makes a big comeback. But because it is soooo stereotypical, makes it automatically clever to subvert it, by just ignoring it and saying, "Alright. It was all just fun. Look at this guys tragic past."
I guess the author had a change of heart later and now desperately tries to undo the plans he had for Dario, to change it into whatever he need him now for. The best course of action might be to simply forget about ch1 Dario and carry on.
Also Ravi was a gigantic dog, when they met. I don't know how this adds up with the assassin following her, but well....might still better mix, than old chapter 1 Dario and what we got here.