Ruler: Master of the Mask / 군주-가면의 주인 / 君主－假面的主人

Ruler: Master of the Mask OST / Special BGM － Princess's Sadness ► Sheet Music

Ruler: Master of the Mask OST 4 － Star and Sun ► Sheet Music

Ruler: Master of the Mask OST / Special BGM － Ga-Eun's Theme ► Sheet Music

Ruler: Master of the Mask OST 5 － Between Seasons ► Sheet Music

Ruler: Master of the Mask OST 6 —I'm Okay ► Sheet Music

Ruler: Master of The Mask OST 3－Even A Little While ► Sheet Music