Just like the Knight, Quirrel is an amnesiac and doesn't remember Hallownest, or his unknown association with Monomon the Dreamer, despite being a part of it in the past. His past is shrouded in mystery that is not made clear in the game. Quirrel is very enigmatic, though incredibly kindhearted, optimistic, and helpful to those he meets, including the Knight, who he guides. He has a calm and peaceful disposition, and although he wields a sharp nail and is an extremely skilled warrior and nail-wielder, he is pacifistic and only ever fights to protect himself and others (such as the Knight when he assists him). Quirrel wears Monomon's mask on his head for the majority of the game, but takes it off to undo the Teacher’s seal after helping the Knight defeat Uumuu. Shortly after this event, Quirrel remembers small parts of his past. Though he is still amnesic about his past and his association with the kingdom of Hallownest, he remains very much at peace, and very optimistic about his adventures, and admits that he is happy and astonished to witness the Knight’s prowess and to journey through Hallownest yet again. He mysteriously vanishes from Hallownest after his final appearance at the Blue Lake where all that remains is his nail.



"𝐻𝑒𝓁𝓁𝑜 𝓉𝒽𝑒𝓇𝑒! 𝐻𝑜𝓌 𝒹𝑒𝓁𝒾𝑔𝒽𝓉𝒻𝓊𝓁 𝓉𝑜 𝓂𝑒𝑒𝓉 𝒶𝓃𝑜𝓉𝒽𝑒𝓇 𝓉𝓇𝒶𝓋𝑒𝓁𝓁𝑒𝓇 𝑜𝓃 𝓉𝒽𝑒𝓈𝑒 𝒻𝑜𝓇𝑔𝑜𝓉𝓉𝑒𝓃 𝓇𝑜𝒶𝒹𝓈. 𝒴𝑜𝓊'𝓇𝑒 𝒶 𝓈𝒽𝑜𝓇𝓉 𝑜𝓃𝑒, 𝒷𝓊𝓉 𝓎𝑜𝓊 𝒽𝒶𝓋𝑒 𝒶 𝓈𝓉𝓇𝑜𝓃𝑔 𝓁𝑜𝑜𝓀 𝒶𝒷𝑜𝓊𝓉 𝓎𝑜𝓊. 𝐼'𝓂 𝒬𝓊𝒾𝓇𝓇𝑒𝓁. 𝐼 𝒽𝒶𝓋𝑒 𝓈𝑜𝓂𝑒𝓉𝒽𝒾𝓃𝑔 𝑜𝒻 𝒶𝓃 𝑜𝒷𝓈𝑒𝓈𝓈𝒾𝑜𝓃 𝓌𝒾𝓉𝒽 𝓊𝓃𝒸𝒽𝒶𝓇𝓉𝑒𝒹 𝓅𝓁𝒶𝒸𝑒𝓈."