Sinful Spoils of Slumber - Morrian

Target 1 face-up Special Summoned monster on the field; change it to face-down Defense Position. If you control a Level 5 or higher Illusion monster, while this card is in your GY: You can Set this card, but banish it when it leaves the field. You can only use 1 "Sinful Spoils of Slumber - Morrian" effect per turn, and only once that turn.