Then she opened her eyes.
As Karyn's expression turned to love Jon thought that the potion had worked but what Jon didn't realise is that Karyn wasn't looking at him. She was looking at her reflection in the mirror behind him.
"Oh hello gorgeous" Karyn said giggling and waving at herself.
Jon was confused and then he looked behind him at the mirror and then back at Karyn and then back at the mirror. That was when Jon realised, Karyn was in love with herself!