Zombie-Loan - Season 1 Episode 2 Want to Die?

Recently, people have been disappearing in Michiru's school, so Shito and Chika investigate the incident. They ask Michiru to help them, but she is more concerned about the ring that she saw around her neck. However, when Michiru finds out that her friend has gone missing, she decides to look for her friend at the school. Later, in the midst of Chika and Shito's battle with the zombie responsible for the disappearances, Michiru is fatally wounded. She wakes up at the Zombie Loan office and finds that her ring his gone, to which Bekkō informs her that Shito and Chika has incurred additional debt in exchange for saving her life.