Kurou Tsunashi is Class 5's teacher. According to him, he has a very bad luck that affects the students of his class. In every year, the class he teaches always get completely wiped out by the eclipses or die for other reasons. (His record: in the year before the last one his class extincted within 10 days) Because of his "curse" his wage was cut by 20%.
He is very eccentric and is fond of his pet cat Shijimi-chan.