Peridot is utterly graceless in bridging the gap between where she was and the proffered spot, her cheeks still blue around the edges. What Feferi has is probably a more honest display of romantic intent than what Peridot has- which is an encyclopedic knowledge of teenage romance tropes just waiting for her to roll them out.

She looks at the snacks, looks at Feferi, and an idea comes into her mind. She picks up a finger sandwich and holds it up in front of Feferi's face, exactly as she's seen one of the campers do to the other camper they were trying to impress. Apparently, feeding other lifeforms is considered romantic.

But Peridot lacks the innate charisma and Feferi may or may not lack the context, and all it really looks like is Peridot turning increasingly more blue and nervous while looking as if she's planning to smash a sandwich into Feferi's face.

She's trying.