One the outside looking in The Slytherin Skittles were some of the meanest of the mean in Hogwarts. But, when you finally get on the inside? You learn quickly how incredibly wrong everyone is about them; that’s what James learned. It took him months to weasel his way in, to get Regulus to trust him. James kicks it with both groups, but it’s clear to his own and Regulus’s friends that James is so helplessly in love with Regulus.
The Marauders and The Pantheon get along when no one is looking. That’s how they came up with this plan. The disowned, estranged son crashed the party to cause a distraction; the Rosier Twins join in. Crouch Jr. and the rest of the Marauders help Regulus sneak out in that time frame. They can not mess this up.
The Black Brothers. Notorious for causing immense trouble, consistently; and always getting away with it. Over half the school hates it, especially Mulciber, Snape, and Avery.