Countess Ilona Kakosy was a powerful vampire and head of one of the five Great Vampire Families. Ilona was killed by Hellboy in 1982.
Countess Kakosy was present at the annual festival honoring Hecate in the spring of 1947. It was at this festival that the Countess and the other heads of the vampire families learned of Baron Konig's violent slaying of Nazi war prisoners throughout Europe. The group was furious with Konig for bringing attention to their kind and executed him before departing.
At some point prior to 1982 the Countess had an encounter with Hellboy in Budapest. She escaped and Hellboy mentions that he has been looking for her for the last 6-7 years.
Hellboy finally tracked Ilona down in Yorkshire in 1982. As Hellboy prepares to stake her, the Countess fools Hellboy with an immersive vision. Hellboy hallucinates being attacked by dozens of skeletal vampires before he is brought before the Varcolac. Kakosy describes the Varcolac as “The King of all Vampir, living and dead, Moroii and Stigoi." The Varcolac is immense, a giant vampire that blocks out the moon. He scoops up Hellboy in his giant hand but Hellboy is able to shake off the vision. Finding himself still standing over Kakosy in her coffin, he stakes her through the heart ending her threat for good.