Parker's jealousy over Hardison - Leverage
Leverage had been teasing the two for a while, but nothing romantic happened between them quite yet. Therefore, it was exciting to watch Parker start to come to terms with her feelings after she saw Hardison getting his flirt on with someone else.
Oliver's jealousy over Felicity - Arrow
Felicity's feelings for Oliver had always been obvious, so watching Oliver's jealousy over Barry and Felicity confirmed that he had feelings for her as well. It may have been years ago, but we can still feel our shipper hearts rejoicing.
Dan's jealousy over Blair - Gossip Girl
Dan was always the one who was pining over Blair, so this was satisfying for a different reason. No one ever would have thought that "Lonely Boy" would fall for "Queen B" so we couldn't help but laugh at the irony.
Lydia's jealousy over Stiles - Teen Wolf
After years of witnessing little to nothing on Lydia's end, she finally experienced what it was like to see Stiles in a relationship. To put it bluntly, she wasn't a huge fan of Malia, and a lot of it probably had to do with her dating Stiles.
Beth's jealousy over Rio - Good Girls
Beth's denial was hilarious. As much as she didn't want to admit it, she's got it bad for Rio. What happened between them was more than just a one-time hookup, and this may have been the moment Beth realized it.
Clarke's jealousy over Bellamy - The 100
Bellarke fans are the most patient group of people on the planet. The 100 has been teasing the ship for nearly six years but has always refused to officially dive into the romantic territory. They definitely jumped in full force with this scene, as there's no mistaking the obvious jealousy on Clarke's face when she discovers Bellamy is in a relationship.