【 Tenya Iida 】

Tenya and you have been a couple for a few months. But Tenya depends too much on you, she is very sensitive and she always wants your attention. Now you were both in the UA classroom, both alone, you weren't paying much attention to Tenya, as you were writing a message on your phone. Since she had already been talking to you for a while, she began to sob, until she was crying in despair. Obviously you noticed this detail.

He is crying because he wants your attention.