The Neco Spirit Neco-Arc (ネコアルク Neko-Aruku) makes an appearance in the Tsukihime series. She often serves as Type-mascot Moon's figure and is a little version of Arcueid Brunestud's cat girl. She portrays Mysterious Neco X (X, Nazo no Neko X? ), a spoof of Mysterious Heroine X/Artoria Pendragon, in the anime series Fate/Grand Carnival.