Welcome to the Impregnable Demon King Castle ~

Alternative

Welcome to the Impregnable Demon King Castle ~The Black Mage Who Got Kicked Out of the Hero Party Due to His Unnecessary Debuffs Gets Welcomed by the Top Brass of the Demon King's Army~ / Nankoufuraku no Maoujou e Youkoso; 難攻不落の魔王城へようこそ ~デバフは不要と勇者パーティーを追い出された黒魔導士、魔王軍の最高幹部に迎えられる~; Welcome to the Demon Castle ; The Impregnable Demon King's Castle and the Expelled Black Mage of the Hero's Party ; The Impregnable Demon King’s Castle and the Expelled Black Mage of the Hero’s Party (Official)