Dukkha
From Tardis Wiki, the free Doctor Who reference
Dukkha was a manifestation of the Mara.
Biography
Dukkha appeared to Tegan Jovanka in a dream. He tempted and tormented her until she formed a pact with him. The deal allowed the Mara too take her as a host, allowing it a physical presence in the real world. (DW: Kinda)
