- You may be looking for the SJA character.
Cousin Ceol, originally called Kelsey and later known as Sojourner Hooper-Agogô, was a young woman from the 21st century who became a space traveller and associate of the Faction Paradox — as well as of PROTEC — during the War in Heaven.
In childhood, Ceol had a friend called Maria. They kept in touch after Maria moved to the United States. Several years later, the two drank lager together on the South Bank of the Thames. (PROSE: Now or Thereabouts)
When she was eighteen years old, Kelsey was travelling with Theo Possible, assisting him with the transportation of his records. They eventually arrived in the Zona Oscura, with Theo acting as a DJ at the Zona Oscura Festival. There, she tracked Jimmy the Mandrill down to a stone circle, but declined his invitation to help him. She later killed him and his partner, Carmen Tranquil, by dropping a giant mirror ball on them whilst they were stunned by the "Katy Manning" Iris' historical performance of "Je Ne Regret Rien" with Theo. Upon her leaving the festival, Theo gave Kelsey his record box, Kelsey joking that she could be called "Ms Funky Pair O'Decks", and she promised Theo that she would make him proud. (PROSE: Party Kill Accelerator!)
Before Kelsey's nineteenth birthday, (PROSE: Party Kill Accelerator!) her dreams were haunted by visitations from her clingy ex-boyfriend Ryan, a priest with an exploding glass face. Desperate to get rid of him, she joined Faction Paradox and was assigned the name "Ceol". She auditioned against several other Little Siblings for the rank of Cousin in an Apprentice-style challenge overseen by Godfather Starch, which included tasks such as evicting a war veteran. Eventually, she beat Little Brother Dominic, became a Cousin, and used her shadow-weapon to kill Ryan. (PROSE: Now or Thereabouts)
Since no one deserted the Faction and lived, Cousin Ceol decided she had to die. Over a long period of time, she hid tiny slivers of her biodata, filtering out all elements tainted by the Faction and selecting pieces small enough not to arouse suspicion. All the while, she hid herself behind a "devoted acolyte" persona.
Ceol found a dodgy, backstreet cosmetic clinic on an insignificant posthuman colony that was scheduled to die in a burst of freak solar flares. She customised the clinic's genetic printer to weave her a new body from the stolen biodata and, once that was performed, she uploaded her consciousness to the new body a few hours before the flares hit. The shell of Cousin Ceol was left with the devoted acolyte persona, and she promptly signed up for a mission to Mohandassa during the House Military incursion, where she was inevitably lost. Cousin Chantelle said that the mission must have even impacted the histories of Ceol's ancestors and descendants.
In the new body, "Sojourner Hooper" barely escaped the planet as a refuge in the last transport ship. She then moved to Pluto, (PROSE: Weapons Grade Snake Oil) where she began working for the Company and became a symbiont with L-Event. (PROSE: Sojourner & Ellie) Ultimately she married Rex Agogô and led a rebellion against the Company, after which she was elected the new president of PROTEC. However, she was blackmailed into joining Christèmas' plan to sabotage the Chance Coteries, where she discovered her rebellion had been puppet-mastered by Scacia De Ren. (PROSE: Weapons Grade Snake Oil)
After death, she and L-Event were resurrected in the City of the Saved, where she became Lady President of one of the factions during the City's Civil War. She ignored a message from Dominic. (PROSE: A Hundred Words from a Civil War)
Behind the scenes
- Ceol is heavily suggested to be an older Kelsey Hooper, a secondary character who appeared in the pilot of The Sarah Jane Adventures who was, therein, set up to become part of the recurring cast, yet never officially reappeared. "Ceol" is the name of the island from which the name "Kelsey" is derived. However, there is no evidence that Obverse Books sought a license from Russell T Davies or the BBC to continue Kelsey's story, and the link is never made so explicit that it couldn't be a matter of namesakes.