It was naïve to think there were no Mudbloods at Durmstrang. There probably weren't many, and they themselves might not know the truth of their blood status, but lies and money guaranteed their presence.
Igor knew this even from his first year, and sometimes wondered in which of his classmates flowed the humiliation of thin, dirty, diluted blood. Idly he wondered, too, what it was like: to wake each morning knowing you were permanently tainted, to live each day knowing that nothing could curb others' contempt for you and everything you stood for.
Later in life, he would find out.