Cluinn is the fan-made nickname for the relationship between Clay and Quinn.
While dealing with her marital issues, Quinn looked to Clayton for support and the two both developed an attraction to each other. Despite this, Nathan asked Clayton not to see Quinn due to all the problems she has in her life saying that she needs time to sort them out and Clayton reluctantly agreed and told Quinn they couldn't hang out anymore. Clayton withdrew from his relationship with Quinn because he didn't want to replace his late wife Sara but they eventually made their relationship official when Clayton started to move past his marriage to Sara. Clay and Quinn's relationship was made official after Quinn helped Clay get Nathan back as a client, forcing Clay to exclaim to Nathan and Haley that he planned on falling "completely and insanely in love with her". They then moved in and their relationship continued to grow closer and did fall in love. They also overcame stalker Katie Ryan and were both shot, but they got through it and became a stronger couple and more in love.
Season 7
Quinn came back to Tree Hill because she divorced her husband and lived with her younger sister Haley. Clay was the sport agent of Nathan, Haley's husband. And they two slowly started a relationship after Quinn moved on after her divorce and Clay from the death of his wife.