Harry Potter: 10 Worst Characters Introduced After The Philosopher's Stone
4. Cho Chang
Cho Chang is the grieving ex-girlfriend of Cedric Diggory who begins to fall for Harry Potter. Harry had a crush on Cho for a long time, and even asked her to go to the Yule Ball with him, but she was already going with Cedric.
In the books, their relationship is given some time to develop and feels quite natural whereas in the film it feels quite sudden and is over as quick as it begins. Harry actually meets Cho in his third year, during a Quidditch match. As far back as that, it's hinted that he has a crush on her.
Throughout the Tri-Wizard Tournament Cho remains a close ally, despite dating Cedric Diggory and she refuses to take part in the bullying of Harry that a lot of others participate in. Later Cho goes against her parents wishes and joins Dumbledore's Army with her friend, Marietta, who later betrays the group to Umbridge.
Cho's relationship with Harry is a lot more awkward in the books as she tries to figure out where she stands with him, while dealing with her own guilt and conflict over liking Harry even though Cedric died. In the film all of this great drama is lost and it's Cho who betrays the DA.
It's sad that a story arc that lasted three books was completely changed and not for the better.