Luka Urushibara

Luka is polite, gentle and extremely shy. He speaks respectfully to Okabe and takes much of his eccentric behavior at face value, including the idea that he is undergoing special training as Okabe's disciple.

He is easily embarrassed, particularly when Mayuri asks him to wear cosplay outfits. His reluctance is complicated by his discomfort with his body and his wish to have been born female.

Luka's quietness should not be mistaken for a lack of resolve. When something matters deeply to him, he can make difficult requests and act despite intense embarrassment or fear.

Luka has no supernatural powers. Okabe gives him Samidare, a replica sword, and assigns him exaggerated training routines as part of their master-and-student relationship.

His shrine duties give him familiarity with traditional ceremonial work, but he is not presented as possessing genuine spiritual abilities.

In some future Beta-world-line material, Luka becomes a member of Valkyrie and takes a more active role in the resistance, far removed from the timid teenager seen in 2010.

Luka is introduced through Yanabayashi Shrine and soon becomes part of the Future Gadget Laboratory's social circle. He is designated Lab Member 006 and participates in the group's discussions even though he lacks the scientific expertise of Kurisu or Daru.

When Okabe begins allowing friends to use D-Mails for personal wishes, Luka asks for a chance to change something deeply important to him.

Luka sends a D-Mail to his mother before his birth, asking her to alter her diet in the hope that Luka will be born female. On the resulting world line, Luka is female. Reversing that D-Mail later becomes one of the steps Okabe must take while trying to escape the Alpha attractor field.

Rintarou Okabe is Luka's self-appointed master. Luka admires him sincerely and harbors romantic feelings for him.

Mayuri Shiina is Luka's school friend and frequently tries to persuade him to model her cosplay costumes.

Eisuke Urushibara is Luka's father and the chief priest of Yanabayashi Shrine.

Kurisu Makise becomes another member of the laboratory circle in which Luka spends time.