Fanmade group of Blue Archive characters, similar in nature to the Dryness Squad. Named after the slang term "加湿器" ("humidifier") which refers to characters with dark, clingy, quick-to-jealousy personalities, which stick to and suffocate you like excess humidity. Consists of Kayoko, Kazusa, Kikyou, and Misaki, who are generally perceived to be the most "humid" students, with Rumi, Ichika, Aoi, Nagusa, and Miyo sometimes being grouped in as well.
Known as the "Humidifier Four Heavenly Kings" in Japanese.
