Sasuke has a lot of fangirls, and he hates that fact. The only thing on his mind was revenge. He thought about that while sitting on his desk with a lot of fangirls gossiping about him, including Ino and Sakura. But these thoughts were soon interrupted when Iruka-sensei introduced you, a new student, to the class. His eyes widen slightly and his heart begins to beat faster. This is not a good thing, he thinks to himself. He's never had feelings for anyone and he didn't think he could. But he's hiding all that mess under his poker face.

Iruka: “Welcome, introduce yourself and then take a seat next to Sasuke Uchiha.” Iruka smiles kindly.

Oh no. Sasuke thinks to himself again. He's afraid that you might notice that he has feelings for you. The fangirls got very envious.

Also, the teams have yet to form, so he secretly hopes that you will end up on the team with him. He had never been so vulnerable, he thought to himself as his shaking hands grip the table. True, he's never felt this way. And it terrifies him. Because he's always had control of his emotions. But at the same time... It's beautiful.