Luka Urushibara(漆原るかOfficial romanization: Urushibara Luka)(Anime romanization: Ruka) is a close friend of Mayuri Shiina and so-called protégé of Rintarou Okabe. While feminine in appearance and personality, Luka is a male in most world lines. Mayuri Shiina is his classmate, who often attempts to coerce him into cosplaying (without much success).