Smoking
"Nana, what will happen you keep smoking?" Hachi asked.
Nana shrugged.
"I heard some people's hair turns gray if they smoke a lot. You'll look like an old lady!" Hachi paused a moment, and then smiled. "Actually, I think that would make Nana look even more mature and cool. And your voice will get all raspy-"
"My voice?" Nana clutched her throat. "I can't lose my beautiful singing voice."
"Of course, if you're smoking that much, your teeth will turn yellow too-"
"When did you get so serious?" Nana spit her cigarette out and crushed it under her boot. "You idiot!"