Hana is an employee in charge of training at a company, currently overseeing orientation for new recruits. Though she's soon to be engaged to her coworker Kimura, this year's batch of newcomers includes some unexpected faces—members of a notorious promiscuous college club from her past. After the training session ends, during a networking party, they slip Hana a spiked drink since she can't normally handle alcohol. Worried, Kimura is forced to leave the training center after an urgent call from headquarters, leaving Hana defenseless. Just as planned, she falls into the hands of her former peers.