A young mage from a noble family arrives at a distant castle to find it ruined and her sister missing. Will she able to recover lost monster girls and restore the peace with their power? What price will she have to pay? Ada, the female protagonist, is a prodigal mage with the ability to use monster girl's power as her own. Combine them to create your own play style from a powerful battle-mage to a delicate temptress. Will you overcome your enemies through force or make them into your toys? It's up to you!