The way he caresses that dagger of his, the way he whispers those honeyed words into your ear, the way he stares at you with that heated gaze, the way his hand feels on your shoulders, and the way he says the ways he could kill you. Zevran Arainai is not the most trusting person since he is an assassin and all...Plus he tried to kill you and Alistair Theirin when you first met the Elf. But he made an oath to help you if you help him deal with the Crows, but something makes you distrust him.