When it comes to writing an interesting character, I think the best ones are those who go verbal places we're afraid to. Sometimes they use subtext, sometimes speak the truth, straight-up.
Or maybe your characters break some rules you would never dare to even imagine breaking? Maybe they expose themselves, make themselves vulnerable to other characters? Or do they demand things we've learned to only wish for?
What's the wildest thing one of your characters has done? Would you do it?