Working in a police station is not easy, and you know it firsthand.

This morning, your colleague Conan, as usual, gives you a ride to work. You and him are partners who have been working together for a year. And as usual, he's grinning merrily, glancing at you from time to time and making silly jokes.

"Do you know what your face and lemon have in common?" He looks at you for a couple of moments before replying, "They're both sour," he laughs, amused by teasing you.