Carl and Chloe first met when Carl was dropping off some marijuana to the Maguire's and Chloe was visiting them to buy some. Carl couldn't help but stare at her and when she started a conversation with him in the Karib's Shop he invited her back to the Gallagher attic to see his marijuana plant's. They got stoned (intoxicated) on Carl's latest crop and made plans to do the same again sometime.
Later, Carl was forced into hiding in the attic from the Maguire's over a misunderstanding that left them thinking Carl had given evidence on them to the Police. Chloe was approached by the Maguires and offered £20 to tell them where Carl was hiding, she took the money and quickly tried to phone Carl, later telling him she though she could take the money and then warn him anyway but he was listening to music and didn't hear his phone.
The Maguire's arrived at the Gallagher house and while the family held Mimi Maguire and her son's back Carl was able to escape into Kev and Veronica's house. Carl and Chloe later met up in the attic again, she commented on him being unhurt and he replied that he could handle himself, she explained what she had intended by taking the money and offered him half of it. Carl refused the money and she replied by asking if there was anything he wanted before climbing onto his lap and beginning to kiss him. Carl then lost his virginity to Chloe and celebrated by smoking marijuana with Lip and Ian and cracking a joke about him not getting "wanker's cramp" (masturbater's cramp) anymore.