He can never understand why she would always act that way towards him.
For Ikari Shinji, Asuka is a thick book waiting to be opened and read. She may seem shallow on the surface, but to him, those actions and that cocky attitude of hers never cease to perplex him. Where is she getting this huge amount of confidence from? Why doesn't she want to be close anyone? Shinji thinks that Asuka is the other end of being an extreme introvert.
She and Rei are both introverted, but they have projected it in different ways. Was being airy a front for Asuka to hide something else that she'd rather keep to herself? She may not be aware of it, but she remains a constant mystery to him, to a teenage boy she calls stupid. That's what makes her more fascinating, Shinji thought. He's a blank canvass lying alone. She would be the vibrant colors that would create a beautiful picture, who would fill the empty spaces of his existence. Her smiles would complement his look of sadness, and her voice would deliver him from silence.
The problem is that a line that separates them from one another remains. It's like she keeps a barrier to block anyone else from coming close to her. She's a turtle who chooses to hide inside her shell rather than to be as free as the wind.
He's not only stupid, he's slow as well. That's what the young Sohryu thinks of her fellow pilot. He keeps on apologizing even if there's nothing to be sorry about and he's always quiet. Deep down inside her lies a desire to get to know Shinji better, but she cannot easily set that feeling free like a butterfly liberated from a cocoon. She didn't want to establish close connections to people because she was always afraid of the responsibility (or did not like the duty) of maintaining those strong bonds. She preferred to be alone so that she would be free of commitment with other human beings.
There was something about this Ikari Shinji, though. He who broke her rules when it comes to knowing and accepting other people. Asuka finds it hard that he cannot realize that himself, the importance and impact he had on her. Were her actions that vague, or it's just that the guy is unbelievably dense? She never longed for human contact like this ever before. She never yearned to share the same feeling with another person like this before, too. The feeling she once wanted to share and pour out to her late mother.
Shinji retains the image of a snail in her mind, ever so sluggish yet gentle. Asuka had vowed to herself that she would wait for him no matter how long it takes for him to reach the end, so that she may open up her world to him.