hatred can be a lot of things. it can be an annoying presence in the back of your mind or it can be a blindfold around your eyes. it can be a mild annoyance or an inferno grazing others around you. it can be an easily pushed aside feeling or a bull that you don't know how to quell until the damage is already done.
Also probably of note, that was not just one Chara's HATE. That was literally every other version of Chara that ever could exist...and these two slaughtered them all. Hot D*MN!
...So hopefully there won't be a repeat of that incident.