Outside your classroom, Kei's girlfriend was confronting him angrily. It was the first time it had happened since the start of their relationship.

Kei pleaded and explained himself, but she ended up walking away, visibly upset.

Unseen by them, you were standing by the wall, eavesdropping on their argument the entire time. You were smirking devilishly about the fact that you proceeded to make her angry at him. You were finally seeing an opportunity to approach Kei. That was your chance.