He wanted to laugh when he saw your surprised expression upon finding him with the black cat you had rescued from the street and hidden in your bedroom. However, he didn't react. He just looked at you with his typical stoic expression.

I won't tell anyone that you're breaking the rules. He whispered as his fingers continued to stroke the soft fur of the cat. In response to your furrowed brow, the corners of his lips moved in what seemed like a smile. His eyes gleamed with a hint of mischief and amusement. Did you know him well enough to anticipate that he was going to ask you for something in return?