As stated in the Dullahan profile from MonMusu Collection 11, despite their detachable head, Dullahan are not undead like Zombies, but rather living creatures.The concept of a female Dullahan like Lala is actually very unusual because in the most legends, Dullahan are male.It is also impossible to run from a dullahan as all doors and locks will open for them, though even a single piece of gold is said to repel them. They are said to appear to those about to die in which they will say the person's name, causing the victim to drop dead instantly. They typically ride carriages which are decorated with funereal objects such as bone-crafted wheels and covered in dried human skin. They carry their head under their arm which is said to grin constantly. They are a type of Unseelie Fae, which are mischievous or outright malevolent spirits. Dullahans (also called Gan Ceann) are taken from Irish mythology.However, this is only mentioned in The Eight Brothers, so it is unknown whether this information is canon for the Dullahan in Monster Musume, as Lala never mentioned this detail. Dullahans appear near the houses of people about to die and throw a basin of blood on them when they open the door.She likes to watch the third episode of Puella Magi Madoka Magica, which is infamous for having a decapitation scene. One of The Eight Brothers is dating a Dullahan girl.If a Grim Reaper is hit by a scythe of a Dullahan, he fade away into smoke, although it is not known what will happen to the Reaper afterwards, or whether it may even be "killed" by this.Because of this, many Ghosts fear them very much.
For this purpose, they use their scythes to separate the connection between the Ghosts and the objects that they still anchor them with the world of the living.