Blood is thicker than water

The next day, Penny was up early despite staying late tutoring Slater. She stayed with him almost all night to make sure he at least understood the lesson. It would be more efficient if he understood one lesson per subject every session. In that case, they could move forward easily. 

Still in her pajamas, Penny carried a pad of paper and headed straight to Slater's room. Her body had grown accustomed to staying up late and waking up early since purchasing her laptop, but she wasn't sure of Slater.

"Knock knock!" Penny announced as she knocked on the door. "Slat — Third Brother, time to wake up!"

Penny knocked a few times and when no one answered, she gazed up at the door. 

'Don't blame me for being ruthless.' Penny took a step back and kicked the door open. 

The door opened with a bang, waking up Slater in an instant.