"Want one, Granger? ...I've got loads. But don't touch my hand, now. I've just washed it, you see; don't want a Mudblood sliming it up."
-- Draco Malfoy (GF18)
The Potter Stinks/Support Cedric Diggory badges were insulting badges handed out by Draco Malfoy.
They were also worn by Hufflepuff and Ravenclaw members in a rare collaboration against Harry Potter when his name emerged from the Goblet of Fire, which was seen by other students as unfair to the Champion of Hogwarts for the Triwizard Tournament who had been chosen first by the Goblet of Fire – Cedric Diggory (GF18, GF19, GF26, GF27).
On one side the badges said “Support CEDRIC DIGGORY – the REAL Hogwarts Champion!” in red letters that glowed brightly enough to illuminate the dark corridor outside the Potions classroom. The badges changed magically when pressed to say “POTTER STINKS” in luminous green (GF18).
Most of the students wear the badges (GF19). This includes all of the Slytherins in Harry’s Potions class, Ernie Macmillan and Hannah Abbott, although Harry notes that Cho Chang does not have one – which cheers him up slightly (GF18, GF19).
After Harry completed the First Task the badges were not as common among the other Houses, but the Slytherins kept wearing them.
Ron was angry at Harry when he couldn’t explain how his name got into the Goblet of Fire, and he was jealous of the attention Harry was getting in the Daily Prophet. One night Harry hit Ron on the forehead with one of the Creeveys’ “Potter Really Stinks” badges and said he hoped it gave him a scar (GF19).
When he imagines admitting that he can’t do the Second Task, Harry pictures Malfoy flashing his “Potter Stinks” badge at him from the crowd (GF26). It seems that Malfoy takes every opportunity to do this, such as a week later in Potions (GF27).
Presumably the teachers didn't know about the badges' dual reading, or they would have stopped the students wearing them. The Slytherins only seem to press the badges when there are no teachers around, or when their backs are turned. --RP
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Harry Potter Wiki: Potter Stinks badge
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