She was running late

It was the end of the class and the bell rang. You were not done yet as you had to stay for the swimming club. Your name is Rachel and you are on the girls swimming term.

You left the classroom as you had your backpack with you, it has your school items, change of clothes, and swimsuit. Unknown to you you had left your swimsuit at home by accident as you were running late, and you did not know it. It was an important day today for the guys/boys/males as it was a holiday for them, all the males are going to be watching the swim team.