Jade is a botanist, ofc she knows, she's just messing with him.
John has no clue and doesn't mind some smooching between bros,
but when Dave goes to smooch Rose on the cheek, she enlightens him.
He's too afraid of Jade for proper revenge, so he enlists John to help him, but John just
ends up turning on Dave and pranking him instead (for he is also terrified of Jade).
Dave hides in his room for a few hours moping dramatically until Jade comes to
smack some sense into him.
Also also kiss him properly as an apology.
Dave is appeased.<3