Kate and Allie are huge fans of Corey Riffin and his band. They obsess over him a lot and cheer for the things that he does and they think of him as their favorite member of everyone in the band. They are also very loyal to him and will go out of their ways to do anything to give him what he wants. Corey is very thankful to have fans such as Kate and Allie and he cherishes them a lot. Sometimes, Kate and Allie can get a bit obsessive and annoying to Corey by stalking him, which makes him feel uncomfortable around them. However, on some occasions, Kate and Allie have stopped liking Corey which makes him feel unhappy and lonely without them. However, when these things do happen, Kate and Allie still prove to like Corey as a friend. When this happens, Corey goes out of his way to try and win them back.
Kate and Allie almost got run over by Trina while she was driving Grojband to the Carnival Derby. Kate and Allie happily texted each other about how excited they were about almost getting run over by Grojband. They were later seen giving Corey a box of money that they made off of selling unauthorized overpriced Grojband merchandise and Corey was very happy and thankful that they gave him that.
Kate and Allie told Corey that they were no longer fans of him because they had now become fans of Cherry Grapestain. They still proved to be good friends with him though. Corey was very disappointed by this and he wanted to get them back. At the end of the episode, after the band's performance, Kate and Allie had gone back to being fans of Grojband again which made Corey feel very happy.
Kate and Allie were seen chewing on Corey's leg which misguided him into thinking that they were zombies. Corey was very terrified when he saw this but he was relieved when he found out that they were really not zombies. Kate and Allie seemed to have taken pleasure from doing weird things to Corey such as chewing on his leg and Corey seemed a bit disturbed after he learned that they did this to him. He was also scared when he saw that they really did turn into zombies. Corey sang the song Zombie Dance, which mesmerized the zombified Kate and Allie and made them faint on the floor as they turned back into humans again.
Kate and Allie become Corey's pit crew in this episode and they help him and his band with their car. Corey thanks Kate and Allie for doing so. Later, Corey asks Kate and Allie do to the favor of stealing Mr. Mooseface from Trina's room which Kate and Allie glady accept to doing. When doing this, Kate and Allie get attacked by multiple lasers and poisonous gasses. This however, doesn't stop them from getting Mr. Mooseface for Corey.El Chewpoocaca. However, Kate and Allie came back to him, worried because it was too late and that all the kids had already been kidnapped. Just then, Corey asked them exactly what they saw only to see they were both kidnapped too which made him jump up in the air and scream in terror. After this, Corey went off to save them from the sewer along with everyone else El Chewpoocaca has kidnapped. Kate and Allie cheered when they saw Corey come into the sewer with them. They rocked their heads to Corey's song. Kate and Allie thanked Corey for saving them from El Chewpoocaca and they told him that they'd stay for the encore but they were scared of El Chewpoocaca waking up so they ran off in fear.
Kate and Allie were seen being fans of Planty's fake Grojband which consisted of a fake Corey. However, they were also hypnotized while watching this. Corey didn't want this to happen so he thought up a plan to set them, along with everyone else free from their trances. and his music and it was Corey's song which broke them free from their trance and made them dance for him.
Allie's mind was possessed by being mind controlled by Trina. This made her join her army which went up against Grojband. Allie walked toward Corey and attempted to implant his mind with the in-brain implant. Corey screamed in fear and ran away.
In this episode, Kate and Allie proved to Corey to be to be bigger fans of Candy Jams than they are of him. This made him feel sad. However, Kate and Allie were still friends of Corey and the rest of the band as they acknowledged them, agreed to Corey's plan, and even sat down and listened to Kin's scary story while Kon tried to scare them with his Ozzy Osbourne impression. However, Kate and Allie were not scared by this. Kate and Allie never ended their fandom for Candy Jams but they were still huge fans of Grojband nonetheless.
Kate and Allie were proven to have voted for Trina because of the fact that she was Corey's sister. Later in the episode, Kate and Allie had relieved word that Corey got kicked out of Peaceville because of Trina. Kate and Allie protested against Trina up to her face, demanding that he returns Grojband to Peaceville. Trina banished them to the sewers for this. Kate and Allie them started up a propaganda to bring Grojband back into Peaceville again. Corey heard them chanting down in the sewers and said that he liked the sounds of their voices. During the song, Kate and Allie were seen in the audience, chanting as Corey sang about overthrowing Trina. The duo even helped throw stuff at Trina to run her out of Peaceville.
Kate and Allie briefly cameoed during the song, holding tickets to Grojband's concert. Corey went right up to them as he sang the lyric "Curl your lips right up to your eyes" and pointed to his mouth making a great big smile. Kate and Allie joyfully looked at him and smiled back.
During the song Love it's in my Heart, Corey came up to Kate and Allie who hated each other at the time and opened up a Valentines day card which played their song. The song was so beautiful, that it made Kate and Allie make up and kiss Corey on the cheeks, making Corey smile. Hearts were seen coming from Kate's head when she was kissing Corey.
Kate and Allie struggled to carry all of Corey's things up Howling Heights Mountain for him. Although, this was a lot of trouble for them, they did not complain. However, it is possible that they only reason they weren't complaining was because their mouths were frozen shut. Corey thanked Kate and Allie for doing this by saying that they were his "Coolest" fans.
During the song, Corey sang out upon the audience and looked directly at Kate and Allie as he sang the lyric "So let us turn the page tonight." Kate and Allie looked at him with a bunch of hearts above their heads.