Bull wasn't just Qunari, he was a big Qunari; by all rights he belonged in the beresaad, he was bigger even than many soldiers. But he was too intelligent, and even being as large and as obvious as he was he managed being a spy.

Being in the middle of Minrathos, surrounded by Tevinter whispers and gasps, made him want to be extra Qunari. If they wanted to see what the rumors and the stereotypes were about, he could show them. He wanted to show then what it looked like when one of their own was clinging to a Qunari's horns, begging sweetly.

Besides, Dorian was inclined to do the forbidden.

His mouth moved, teasing every place he knew got Dorian flustered without offering actual relief. He made sure every whisperer could see him and the bruises Bull left.