Due to the high suicide rate among youths in Japan, the government implements experiments to uncover the causes behind the high suicide rate. Children are selected and placed in a YSC facility under constant surveillance. At the age of 10, the children are then give a detonator with a red switch. They are told if they press the switch they will die immediately. Most of the children under the experiment, eventually presses the switch and dies. After the completion of the experiment 6 kids remain who did not press the switch. The 6 kids are; strong-minded Masami, weak Naoto, hot-tempered Hiro, impulsive Ryota, wheelchair bound Kimiaki and Aiko who is always thinking of her parents. These 6 kids survived even though they were pressured by project manager Tsukuda to press the switch.

Wakabayashi Ema is a temporary employee who works at a banquet hall where glamorous celebrities gather. But, she loses her job after protesting against her superior's sexual harassment towards a junior employee. Wandering, Ema visits a perfume shop run by a mysterious woman named Shirashi Yayoi, also known as the "witch." While helping in the shop, Ema realizes that she holds the key to shaping her future through the words and scents given to her by Yayoi. Ema moves to work for a fragrance company, where she reunites with Ren.

Saya Suzuki is an ordinary employee working at a hotel. She falls in love with her elite boss Susumu Tsuge. Through their romance, Saya Suzuki grows as a person.

Ai Majima studies AI at a university. She needs to collect data for her graduation thesis. The theme for her thesis is "Ways to make women feel better according to differences in the brain between men and women." For her research on her thesis, Ai begins working part-time at a wedding hall.

A police detective Shoukokuji Ryuuya from the first section of Metropolitan Police Department is tasked to investigate the murder case of a woman which takes place at a grand party held by a big-time actress but faces the hurdle of finding the true culprit among the large pool of suspects.