“So dance with me, just say-”
“No!”
As far as we know, Pearl never danced with a human before. We only see her dancing with the gems and no one else.
So to have Greg of all people, insist on dancing together, she snaps. She believed fusion was the ultimate connection between gems. Yet Greg was able to connect with Rose on another level.
Fusion is kind of a big deal for her. Same with Garnet but on a different standpoint. She hated that, so having Greg attempt to dance with her in order to bond was out of the question.
To have Pearl finally offer her hand to Greg to dance is a great step foward. They finally fused. Their friendship is blooming.
You know, if you said fusion was just friendship when rainbow quartz happened, rosepearl shippers would have lynched you. His isn’t just friendship, pearl “fusing” with greg means she’s developing feelings. It’s probably not even out of nowhere either because remember how her first dream was about greg?