A foreigner born in Greece and raised in Ireland, he has a love for Japan.
He is known as Yakumo Koizumi, which is his Japanese name. He appears to be friendly and cheerful on the outside; in reality, he is a black-hearted person.
Although he earns his living as an English lecturer at Tokyo Imperial University, he is solely interested in the study of Japanese Mononoke. He spends his days and nights collecting information on Mononoke.