Slug Club

The Slug Club was made up of Horace Slughorn's most well-liked and sometimes famous students at Hogwarts School of Witchcraft and Wizardry. Professor Slughorn, who taught Potions at Hogwarts from the 1920s-1981 and again from 1996-pre 2016, sought students who were well connected, held fame, and/or showed true promise in some field(s) of magic in his eyes.

These select students were invited to parties (such as the particularly lavish one held on the 20th of December, 1996) where Professor Slughorn would then weed them out further. He was sure to keep in touch with those who "made the cut", even after they had graduated, as they would often provide him with useful information and/or various luxuries.

Meetings
"Harry, Harry, just the man I was hoping to see! I was hoping to catch you before dinner! What do you say to a spot of supper tonight in my rooms instead? We’re having a little party, just a few rising stars, I’ve got McLaggen coming and Zabini, the charming Melinda Bobbin — I don’t know whether you know her? Her family owns a large chain of apothecaries — and, of course, I hope very much that Miss Granger will favour me by coming too."

- Horace inviting Harry Potter to a Slug Club gathering



Along the course of the school year, Professor Slughorn would hold various club get-togethers (most often dinners with fine food and around 10 student-attendees). Slughorn would lead the conversation in order to get to know the members better and encourage them to associate with one another. For the grander parties he would invite famous former members, such as professional Quidditch player Gwenog Jones.



Professor Slughorn's aim was to cultivate talent and give his favourites a nudge toward fame and fortune, hoping to reap the benefits of his connection to them once they became the "high fliers" he expected them to be. On the 20th of December, 1996, there was a lavish party for past and present Slug Club members held in Professor Slughorn's office at Hogwarts. It was the only get-together of the club that Harry Potter attended. After Harry's failed attempt to get a particular memory out of the Professor, Slughorn apparently stopped these meetings in order to prevent giving Harry another attempt.

It is unknown what became of the Slug Club when Severus Snape became headmaster during the 1997–1998 school year. It may have been disbanded due to the return of Educational Decree Number Twenty-Four, though the decree technically only affected student-founded clubs (such as Dumbledore's Army). Under the authority of Minerva McGonagall beginning in 1998, it is likely that Professor Slughorn stayed as Potions Master and Head of Slytherin House at Hogwarts. Due to his nature, the Slug Club was likely reinstated (if it was ever disbanded).

Students not accepted

 * Marcus Belby – His uncle Damocles invented the Wolfsbane Potion, but Marcus had not spoken to him in a long while as his father and uncle were not on good terms. Belby was nevertheless invited to one of the club's supper meetings, but by the time of the Slug Club Christmas party, Slughorn had Belby passing out towels in the loo.
 * Neville Longbottom – His mother and father (Alice and Frank Longbottom) were once well-known and loved Aurors, but Neville showed none of their talent in this field (presumably his adeptness for Herbology never came up in conversation).
 * Theodore Nott – His father was an old friend of Slughorn's, however after being outed as a Death Eater Slughorn presumably decided against inviting Nott into the club.

Benefits for Slughorn
Helping others become famous gained him influence (such as being able to recommend the next junior member of the Goblin Liaison Office) and various benefits (such as free tickets to any Holyhead Harpies match or a box of his favourite crystallised pineapple). Horace forechose to obtain things he desired by using his connections to make his life comfortable and cosy, rather than obtain them directly.

Benefits for students
Being in the Slug Club is both an honour and an opportunity due to its exclusiveness, and with Professor Slughorn’s connections they would likely have first-rate careers ahead of them (if they possessed proper talent to begin with).

Disappointments
Although Slughorn has an eye for talents and potential, there are times where such students disappoint him. Slughorn has no desire to affiliate himself with criminals, and as such, when Lucius Malfoy and Nott were caught red-handed as Death Eaters, he severed ties with them and did not invite their respective sons to his gathering. He also thought he could trust Severus Snape, until the latter murdered Albus Dumbledore, which greatly shocked Horace, until Snape's name was cleared a year later.

One of Horace's most disappointing students was Tom Riddle, who did not take up Slughorn's great job offers and instead worked as a shop assistant, and then severing contacts with the professor, thus leaving no benefits for either, much to Slughorn's chagrin.When Riddle resurfaced as the Dark Wizard Lord Voldemort, Slughorn became visibly disturbed, especially when he learned that Voldemort used Slughorn's information to create multiple Horcruxes. So much shame that Horace felt for misjudging Tom that he resigned from his post as professor and modified his memory to give himself a sense of false comfort.