>>53272572Let me spell it all out for you anon. Spoilers inbound since I doubt you have any interest in actually reading it.
The arc begins with Pearl and Diamond at some comedy competition. They win a prize. They end up running into Prof Rowan and Platinum's dad on the street where they have an accident and end up switching their prize with the directions for Platinum's bodyguards who just happen to also be identified by their green and red scarves. Pearl and Dia get there expecting a tour guide on an all expenses paid tour of the region, while Platinum shows up thinking they're her bodyguards and they'll be taking her to the summit of Mt Coronet. It's all a gag that they keep up for like over half of DP.
But the real bodyguards have been searching for Plat in the background the whole time. Eventually they run into Pearl and Dia, where though Dia already figured out what was going on on his own, Pearl learns of what was going on. By this point the three are already very close to each other so the two of them swear to Platinum that they'll guard her with their lives. She still doesn't know that they're not her real bodyguards so she's confused. She only learns of this much later where at that point she's cool with it because she has such trust in the both of them.
Their trio functions like this. Pearl is the leader, and Plat is the one doing the gym challenge, while Dia is mostly there for comedy, but he is also the one who steps up for important moments and is ultimately the one with the most characterization and I would consider him the "mainest" main character.
In total the three of them have very high chemistry which makes the whole arc very entertaining. Pearl is the loud tsukkomi, Pearl is the slow boke (or is it the other way around? not sure), and Plat is autistic but pretends not to be. Honestly probably the most well written arc even if I prefer RS 