Every time Leo's sword and Quill's electric-made touches each other, electric shocks would be sent to Leo, causing him an occasional strength loss. He would nearly lose grip of his sword and unwillingly let Quill land an attack, a decisive one.
"What's wrong? You seemed as though you're exhausted." For some quiet reason, Leo's strength, he feels like it was slowly getting extracted out of him as the fight against Quill lengthened. There was a mockery of Quill's word, which the latter blatantly shows.
Leo let out a grin on his face. He tightly clutched on his sword and answered Quill's question, "yeah," he replied coldly. "I'm getting tired of fighting you." Sarcasm and mockery filled Quill's head and, anger once again rose from inside him.