In their conversation before the fight, Damien had said he wanted to practice his skills. He wanted to keep himself strong. Levi was one to give those lessons, intentionally or not. He wasn't surprised when he felt his blade strike flesh and it was to Levi's credit that all it did was tear Damien's shirt. He could have lopped off his head before Damien even had a chance to blink, as far as Levi was concerned. Levi was impressed, however, when Damien recovered instantly. A man used to battle, then, or at least, one good with feigning that he was.
His reaction, however, was predictable. It was a good move. Trying to judge one's opponent with a move like that was a good way to understand them. Levi had used the skill himself when he'd been a kid, learning how to fight and to survive in the underground. His size also helped matters. He would be good, however, and not use his 3D Gear to his advantage at the moment. That would be his handicap, because if Levi was in the air? The man wouldn't stand a chance.
"Swords held like yours are good in front defense, but what about from the side?" remarked Levi coolly, referring to the sword in the horizontal position in front. He rolled easily with the feint, lowering his center of gravity to keep himself balanced and to parry the other blade with the one in his right hand. He needed to show this kid that if he, as a human, could move like this, then what if someone else could move faster? Or something else could move faster?
In a move that he was famous for, Levi moved. And he moved fast. Almost too fast to catch his individual movements. He spun gracefully on his feet, though they were still in a defensive position. His knees were lightly bent and his heels were what he used to spin himself. It wasn't quite the same as his spinning flip that he did when striking down Titans, but it was a close replica. Keeping his right blade still touching Damien's, Levi spun to the left, using this momentum to propel him forward and closer, getting behind Damien's defense. His left blade moved forward, aiming for his neck. Levi wouldn't let his blade touch the other this time, though. He would stop just a centimeter shy, just to let his point be known here.
That was, unless Damien could react fast enough and parry his blow before it came close. He hoped the other man could do that. So far, his reaction time was impressive. More than one recruit had wet himself fighting against Levi for the first time. And Eren, as capable a fighter as the young man was who could shift into a Titan, was terrified enough of Levi to know that just because he could shift into a Titan didn't mean that he had to do so. Levi's skill went unmatched back home, but he let his actions speak for themselves.