“Jealous, sister? Or just over protective of your little student?” Luna lifted her hoof up off of the unicorn in question. Twilight quickly got to hers, ears pinned back and flaming in embarrassment as she looked at her teacher.
 
Celestia stared back for a moment before turning her gaze to her nocturnal twin. “When we agreed on teaching Twilight to be a little more battle-hardened in case of another emergency, we did not agree on anything remotely similar to this.” She leered at her sister, flicking her horn at the patch where Twilight previously lay.  
“And so you decided to simply come to check up on your prized pupil? After we explicitly asked not to be disturbed? We think your obsession with her has reached its peak,” Luna sneered, walking with cold intent towards her sister, rising up to Celestia’s challenging stance.
 
The white mare bristled further “Concern is a better word. With a right to be by the look of things.”
 
“We did no harm to your student,” Luna shot back bitterly. “All mal-intent was staged.”  
“Mal-intent is not what I’m concerned with, and you know it.”
 
“So jealousy it is then,” Luna tittered. “Did we steal her first kiss? Was that meant for you?”
 
Celestia’s hoof slammed against stone floor with enough force to break the slab, but Luna remained unfazed; “We didn’t hear Twilight complain.”
 
The blast that resulted sent the darker goddess flying across the room. Her fate had been Twilight’s not moments before, but Luna shrugged the attack off much more quickly. “Touch a nerve, Celestia?”