Urushibara Ruka♂

Ruka is a friend of Okabe. His appearance is that of a female and he acts in a feminine way due to his upbringing, wearing girl's clothing within and outside his father's temple. He is also a close friend and classmate of Mayuri's and is often asked to try on her cosplay costumes, but as he is quite shy, he generally refuses. He is unsure of his feelings towards Okabe, who calls him by his nickname, Rukako, containing the feminine suffix -ko, to denote his feminine appearance, and thinks of Ruka as his pupil.