JAJR is the one-sided pairing of Jon and Jessica as a couple.
Jon thinks Jessica is a complete moron and will do mostly anything to stay away from her. Occasionally, Jon will allow himself to go near her, but only because he enjoyes pulling many pranks on her. No matter what he does, he is never able to draw her away from him. He would try anything just to get her away.
Jessica always thought she could get any boy she wanted, and when she noticed Jon well, she thought she could have him too. When she realized that Jon only had eyes for Liz, she knew there had to be a way to win him over, because she felt she was so much better than Liz. She typically tries to keep Liz away from Jon, and Jon away from Liz. She will try anything, just to keep Jon by her side, which almost never works.