Lets see now, Pearl is massed produced servant class gem that is for all intents and purposes is disposable. She is likely infatuated with Rose since she was probably the first person to show genuine concern over her welfare and treated her a person instead of a tool.

Lapis was a damaged gem who was no longer considered person and was only deemed fit for becoming a tool. Steven was the first person since her captivity to treat her as an actual person and frees and restores her. Lapis then feels gratitude towards Steven and is willing to trade her freedom in order to protect him.

The writers better damn well have an episode of Pearl seeing characteristics of herself in Lapis or I'll be an uncle grandpa.

Rose's face… She looks pissed but disgusted. I always imagined she'd be taken aback, but a bit sad. And instead, she's kind of like "ew tf are you doing???"