Of all the imprinted couples, Quil seemingly has to wait the longest for his soulmate to mature.
Quil Ateara V
Quil Ateara V was born and raised in La Push. His father, Quil IV, passed away during a storm, and Quil was raised by his grandfather and mother. He had Jacob Black and Embry Call as best friends, but they had a brief fallout when Jacob and Embry phased into wolves.
- "Quil will be the best, kindest big brother any kid ever had. There isn't a toddler on the planet that will be more carefully looked after than that little girl will be. And then, when she's older and needs a friend, he'll be more understanding, trustworthy, and reliable than anyone else she knows. And then, when she's grown up, they'll be as happy as Emily and Sam."
- ―Jacob, on Quil and Claire's relationship.[src]
Jacob mentions Quil's and Claire's first encounter to Bella in Eclipse. Given the large gap in their respective age, Emily and Bella find their relationship scandalous and have a hard time not making judgment, but Jacob assures Bella that Quil is simply being an older brother to her, with no romance in mind; and as she grows, they may become a couple and that Quil is not aging for the moment due to his active shape-shifter physiology.
In the middle of Breaking Dawn, Claire has her 3rd birthday party and Quil is invited and Claire got make-up for her birthday which Emily persuaded them to try out on him. After the party, they play at the beach and encounter Jacob.
Jacob tries to persuade Quil to date other girls while Claire is still young, but he finds himself unable to notice other girls now. When Jacob, Seth and Leah first separated from the pack, Quil is only unable to join them because of his ties to Claire, who also seems to be very possessive of him.
Jacob said that he had seen Quil play peek-a-boo for one hour straight without getting bored.
They make an appearance together in Breaking Dawn - Part 1 with the rest of the pack at First Beach.