Celica Clayton

Celica Clayton, renowned as the "Monarch Adventurer" throughout World's Odyssey, is a young NPC with tremendous talent. She has a heart, and meets Shina and company on her journey alone in pursuit of Odyssia, which continued even after the world was infected with bugs. She is the charismatic presence of the Adventurers. Arata finds out that Celica shares a striking resemblance to a missing foreign idol.

End Quest
In End Quest, a Japan-exclusive preorder bonus for Death end re;Quest, Celica originally battled in a more pragmatic manner; she would allow NPCs to be killed by monsters in order to study their attack patterns. Part of her interactions with Iris included modifying her personality to be more "in-character."

Death end re;Quest
Celica is first encountered in Chapter 5. After the party helps her right her boat, she joins them on their quest to reach Odyssia. Arata, having previously heard a news report regarding the disappearance of foreign idol Chloe Aaron, quickly notes how similar they are in appearance.

In Chapter 10, the party reaches Odyssia. While the rest of the party is in awe of the legendary sky capital, Celica appears less than pleased. At the same time that Arata is assaulted by Aphesis at Summer Life, Celica turns her sword on the party. She reveals that she had already reached Odyssia before meeting the party - hence the damaged Terminal Stones that hindered the party - and found nothing but monsters. Figuring that the "real" Odyssia was somewhere even further beyond, she tried her hardest to search for more, breaking her ribs in the process, until she managed to pierce the game's boundaries and end up in a black void. The thought of the legend of Odyssia being a lie caused her despair to overload, threatening to glitch her out before she met Victor Tailman. Claiming to be God, Victor instructed Celica to capture Shina Ninomiya, promising to make World's Odyssey real in exchange.

Upon recalling these events, Celica proceeds to glitch out and fight the party. As the party subdues her, memories of another world flood her mind. Chloe Aaron hated her father, but believed that doing his bidding would lead to her finding more in life. So she continued to sing and push herself, at the expense of her family, friends, and classmates. She finally obtained fame and fortune, but it was no replacement for love, and Chloe was left feeling abandoned.

She takes her lost despair from her buggy, and appears to be ready to continue the journey, but Victor reveals that he has taken the Mr. Enigma avatar from Arata Mizunashi. He hijacks Celica's personality, causing her to become a mindless killer; the brainwashed Celica proceeds to end the lives of Al Astra, Lily Hopes, and Lucil Filarete. Right as Celica prepares to kill Clea Glaive, Clea reveals that she knows the emotion that her own buggy is suppressing and, tapping into her suppressed courage, sacrifices herself to eliminate Celica.

It is revealed, however, that everyone survived the encounter and were rescued by Ending Engage. Chloe joins Arata and the other members of the party in subduing Iris. One campfire scene in Chapter 11 has Celica feeling remorse for what she did to the other party members, but Al convinces her to stay.

In Celica's ending, time has reversed to before the events of the story. Arata finds himself at a press event in which Aggle announce the Alice Engine. When attempting to return to Enigma, Chloe apologises to Arata for being late to the tour as she was stuck in traffic, though he doesn't recognise her until she takes off her sunglasses. Chloe doesn't remember Arata, however.

Death Ends

 * If the party challenges Celica for her boat in Chapter 5, Celica obliges before effortlessly decapitating everyone.

Trivia

 * Mary Skelter 2 gives Red Riding Hood a costume based on Celica as part of its "Death End Attire" cross-promotion. Like Celica, Red Riding Hood fits into the "cool big sister" character archtype.