"House-elves does what they is told. I is not liking heights at all, Harry Potter ...but my master sends me to the Top Box and I comes, sir. ...Master - master wants me to save him a seat, Harry Potter. He is very busy ...Winky is wishing she is back in master's tent, Harry Potter, but Winky does what she is told. Winky is a good house-elf."
-- Winky at the Quidditch World Cup before she was sacked by Mr. Crouch (GF8)
Winky, a female house-elf who until recently worked for the Crouch family, has enormous brown eyes and a nose like a tomato (GF8). Her mother and grandmother were also Crouch family house-elves (GF9, GF21). For years, Winky took care of Barty Crouch Jr., who was held in the Crouch residence under the Imperius Curse by his father. Nevertheless, the elder Barty Crouch sacked Winky when she was found holding a wand after the Quidditch World Cup in suspicious circumstances, which not only publicly associated him with Dark magic but demonstrated that her guardianship of his son might be unreliable (GF8, GF9, GF35).
Winky has since come to work at Hogwarts, but she is considered a disgrace by most of the other house-elves and has taken to sitting on a stool beside the kitchen fireplace and getting drunk on butterbeer. Her loyal friend Dobby has looked after her as best he can, but her distress as the deaths of the last members of the Crouch family hasn’t helped (GF21, GF28, GF35, OP18).
She was good at keeping secrets for the Crouch family, and doing what she was told.
Other canon notes and references
Unlike Dobby, Winky had a hard time adjusting to her life as a free-elf at Hogwarts. She still missed the Crouch family even though they mistreated her and took her for granted. She drank so much Butterbeer in the kitchen (instead of working) that sometimes Dobby had to take her to the Room of Requirement where he "found antidotes to Butterbeer there, and a nice elf-sized bed to settle her on" (OP18).
J.K. Rowling stated in 2004 that Winky would never get over her problem:
Question: Will Winky ever recover?
JK Rowling: Poor Winky... she'll never be entirely cured of her Butterbeer addiction, I'm afraid (WBD)
But in 2007 there was more hope (or just an inconsistency):
Question: What ever happened to Winky?
J.K. Rowling: She's still at Hogwarts, and she was one of the oncoming house-elves who attacked the Death Eaters in the final battle.
Question: Does Winky still drink a lot of Butterbear?
J.K. Rowling: She's dried out a bit now. (BLM)
On Episode 11 of the Mugglenet Academia podcast, the discussants and particularly Dr. Louise Freeman noted that Winky can be understood as suffering from traumatic stress (in her drinking) and/or Stockholm Syndrome, whereby Winky can to care for and idolize her "captors" (in the Crouches). This may explain why she may never be able to overcome her distress at being dismissed.