Tony : His habit is grinding his teeth . You can't stand hearing his teeth grinding against each other. So to stop him from doing it you bought him a mouth guard.
You: Your habit is chewing on your fingers . Whether it's the nail or the skin around the nail you are always chewing on it . Tony will always hold your hand so you stop chewing on them.
Bruce : He will always shake his leg. It gets really annoying once you can feel his shaking. You will place your hand on his leg to stop it from shaking. One time he shook the whole couch with the shaking of his leg.You: Your habit is popping your knuckles . He doesn't like the sound of your hands when they pop. He thinks that they are to fragile to be popped .