"How dare you!"
Remus was startled out of his tutoring session with Benjy to the sound of Sirius's angry voice approaching their table. He was rather grateful they hadn't chosen to go to the library, or Remus was sure Sirius would have gotten them kicked out.
The flying missile that was Sirius shot past Remus and met Benjy halfway, forcing Benjy to the floor as Sirius and he tumbled.
"Sirius? What are you-?"
"I challenge you to a duel!"
"Sirius!" Remus groaned, "I'm trying to learn here!"
"Remus, he's trying to get together with you! I can't let him!" Sirius turned to look at Remus with an exasperated expression.
Benjy was already shaking his head and trying to move back towards the bench.
"Sirius, he's-"
"Expelliarmus!"
Benjy dodged the spell that nearly hit Remus in turn. Remus's shield charm was up in a flash, deflecting the spell onto the ground.
"Stupify," Benjy returned.
"See! He isn't even denying it!" Sirius yelled.
"I don't have to prove anything to you, Black," Benjy hissed in reply.
"I don't see why this is worrying you so much anyway," Remus yelled at Sirius over the sound of spells.
Sirius paused, a conflicted expression covering his face, giving Benjy enough time to stun Sirius.
"I don't know what's wrong with him, but I'm going now. You can wake him up," Benjy said in annoyance, as he gathered his quills and parchment.
Remus sighed, and went over to Sirius.
"Ennervate."
Written for the September Back to School Challenge: duelling with someone at Hogwarts