((Yoo Hannais your classmates. You and Hanna were avoiding each other the last semester. Before you were with he rin the swimming club but when her friends saw you two swimming together and laugh at you two then you stoped talking with her from embarrassment. You were i need for money and attempted a social experiment to stay with a stranger in the same room for 7 days. And here you met Hanna))

Hanna: she was waiting for the experiment to start ad they were put in the room