Mitsuki Konishi is a villain from the video game The World Ends With You and an officer of the Reapers. She serves as the Game Master during the third and final week.
Mitsuki Konishi is a high-ranking officer of the Reapers who aims to climb the ranks at all costs. She acts like a secretary to the Conductor, Megumi Kitaniji. Konishi reveals her true colors during the third week when her minions "kill" Beat's kid sister Rhyme, then take her soul as a hostage, imprisoning her in a badge. She then forces Beat to complete the week's missions, under the threat of erasing his sister's existence forever. When Beat completes these tasks and retrieves the badge, it proves to be a fake. She is responsible for death of a sympathetic character, "erasing" 777 for failing to defeat the heroes. When finally cornered, Konishi reveals her true motive: to overthrow the current Conductor - who, by contrast, is a Well-Intentioned Extremist - and gain unchecked power over the Underground plane. With her dying breath, she aims to inflict further suffering on Beat - who had infuriated her by refusing to play to her script - by attempting to convince him that his sister never truly loved him and that his efforts were pointless.
She is arguably the most evil of the Reapers who at first appears to be very loyal to the Composer, often demanding respect when the Reapers of lower status address them. But this is just a ruse; she's truly very cold and manipulative and will do anything she sees fit to meet her own ends. Because of her passive personality and her relatively cold demeanor, she has gained the nickname "Iron Maiden"