Мачі Кьоко

A shy dullahan whose head is always detached from her body, which has a blue flame coming from where the neck should be. Since she can't move her head by herself, she is always longing for contact with others. She develops a crush on Tetsuo, due to his kind and caring nature. She initially found it hard to make friends as people found it awkward to talk to her without bringing up her detached head in some way, despite her own acceptance of the concept and desire to joke about it. Incidentally, she does possess a neck, which allegedly exists in another space and serves as a wormhole between her head and body.

(Source: Wikipedia)