After Duncan hanging out with gwen thing.
Courtney is a lot of things but forgiving is not one of them.
I just read a Fan Fic on wat MIGHT happen.
"Oh, princess." Duncan called. "Aren't you thrilled to see me?" He asked. Courtney immediately forgot about her little fit and rushed over to Duncan. She hugged him, but when he leaned in for a kiss, she slapped him.
"What was that for?" He asked.
"That was for hanging out with Gwen so much." She replied. Duncan rolled his eyes. "You'll forget about that in about five seconds." Duncan shrugged.
"What makes you think I'll forget? I hold grudges for a very long-," Duncan interrupted her by kissing her forcefully.
LOL, I doubt that will happen though.