A Belkan Bug Summoner. Lutecia travels with Zest and Agito. The 3 works with Scaglietti on getting Relics, but Lutecia is only of the 3 that trusts Scaglietti and his Numbers. Zest and Agito have tried to convince that Scaglietti isn't worth trusting, but have been unsuccessful as Lutecia views Scaglietti as a kind man. Because of her trusting attitude, Scaglietti has been able to manipulate her actions to an extent. She and Zest have been referred to on one occasion as Relic Weapon Experiments by Scaglietti. And as it turns out, she and Zest have been searching for very specific Relics, Lutecia specifically in search of Relic number 11.

Spoiler

As revealed in Episode 24, she is the daughter of Megane Alpine, who was involved in the Combat Cyborg incident where Zest was presumed to have been killed. In the Epilogue she is seen living with her mother. She is named for the Renault Lutecia, known in most markets as Renault Clio. Alpine was a sports car brand bought by Renault.

(Source: Wikipedia)