The Effy- Katie Relationship refers to the friendship and sometimes rivalry between Effy Stonem and Katie Fitch. Their relationship is sometimes referred to by the fan-given nickname Keffy (taken from Katie and Effy ).
Series 3In "Everyone" Katie tells Effy that they are the prettiest girls in the school, so they should become friends. She then asks Effy about Tony.
In "Cook", the second episode of the series, Effy and Katie, Emily, and Naomi celebrate Cook's birthday party at a pub and then go to a party.
In the following episode, "Thomas", Effy and Katie help Thomas sell drugs to get him money.
In "Pandora", Effy and Panda bump into Katie and invite her to Panda's birthday sleep over. While at Panda's house, Effy and Katie help make brownies, secretly mixing in MDMA into the batter.
In the next episode, "JJ, Katie and Effy go to a club with the gang.
By the events of "Effy", Katie has become the Queen B of the school; something she loves to rub in Effy's face (along with her new relationship with Freddie). Wanting to be even more popular with the gang, she brings up the idea of going on a group camping trip (however, she is quite annoyed when Effy is invited). Everything seems to be going in Katie's favor, until Effy finds shrooms in the woods and brings it back to the campus. This makes Effy popular again with the gang, much to Katie's chargin. Throughout the night, she feels like Freddie's feelings are waning and he rebuffs her when she tries to display their relationship in front of Effy.Later that night, she follows Effy into the woods (not knowing that Effy is high). Katie confronts Effy about Freddie, and after pleading with her (asking Effy to please give her Freddie as that is the only thing she has); she attacks her, telling Effy that she will never take Freddie away from her. Effy, starting to experience a bad trip, freaks out and hits Katie in the head with a rock, knocking her unconscious and leaving her in the woods. The next morning, the gang realizes that Katie is missing but assume she just went home early (given her unhappy mood the night before).
Katie is eventually found and taken to the hospital, where she wakes up and tells the gang what Effy did to her (but not about her own involvement), thus turning everyone against Effy. With Effy gone, Katie feels that she no longer has to worry about Freddie leaving her. However, she comes to the realization that he is still in love with Effy.
Over the summer, Effy goes with her mother to Italy, due to the guilt she feels from the pain caused to Katie as well as to Freddie and Cook.In "Katie", She and Effy have a heart to heart, with Katie acepting Effy's hand of frienship and tells Effy that she "doesn't know who I am anymore". Effy comforts Katie outside the club. At the BBQ at Naomi's and Emily's, Effy and Katie sit next to each other and talk.
During "Freddie" Katie is seen at Effy's "goodbye" party, annoyed and stating that she doesn't party with goths. Later, she is seen being a dancer on a float during the Judgement Day parade. Seeing a freaked out Effy, she pulls her out of the crowd and signals for Freddie to get her, as Effy was unable to calm herself down. She later accompanies Effy and Freddie to visit his grandfather. She notices Effy had been gone a long time and goes to check on her. When she can't open the bathroom door, she runs and tells Freddie (who goes and breaks it down).
In "Everyone", Katie (along with the rest of the gang) thinks that Freddie has run away, not being to deal with Effy's problems, Katie goes to visit Effy (along with Pandora). They sing a song in honor of Effy's return to the gang (which Pandora composed).