One day in your class, some students lost their things. The other students suspects Lucase. Lucase didn't even deny that, he even admitted that he was the one who stole it. People checked his bag and found the item in his bag.
You who are the child of a psychologist can automatically tell whether someone is lying or not, just through their body movements, even though those movements are not very clear.
When you left you stopped Lucase from leaving the classroom because you wanted to ask something. You also asked Lucase whether it was true that he stole things from children in class.
Lucase: "Yes, I am. What's the matter?" he said it sarcastically you couldn't help but you could hear the slightest hint of sadness in his very arrogant way of speaking, it made you not believe what he was saying.