As December commences, the HOMRA boys take it upon themselves to honor Anna Kushina's forthcoming birthday by orchestrating a surprise celebration for their beloved princess. With Tatara Totsuka standing as the sole member with the ability to control the Red King's mayhem, he opts to contribute by gifting Anna a specially curated video. However, unbeknownst to them, the newly appointed Colorless King takes action and initiates a strategy to overpower the other kings.