Maris Stella

A curator at the Tokyo Art Museum. Maris first met Reiji during an investigation involving the 'Girl of the Shell.' She rarely talks and usually speaks in broken Japanese but becomes strangely eloquent when discussing paintings.

She is the daughter of an Italian missionary, Christopher Berg Stella, and a Japanese nun, Katsuragi Motoko. Her personal history includes overcoming mutism, aided by Rokushiki's treatment, and her late sister, Celestial Stella, was Rokushiki's lover.

Based on the official site and Wikipedia