Yuuko Hiiragi

Age: 16
Height: 157 cm (5'2")

A second-year student at Fuji High School and Saku's classmate.

A glamorous, beautiful girl who exudes a natural princess aura, considered by those around her to be Saku's 'first-wife.'

She herself loves Saku dearly and watches over him more closely than anyone else.

(Source: Official YouTube, translated)