Not much is known about Yuka Takaoka's early life, besides that she was born an only child and, after dropping out of university to pursue a career in the Japanese Bar and Service industry, obtained a management position at a girls' hostess club in Shinjuku Ward, Tokyo.
In October 2018, she met her boyfriend Phoenix Luna, who was a bar worker at the Fusion By Youth nightclub, located in the Kabukicho red-light district.
Original reports stated that the couple moved into an apartment together on the fifth floor of Plaire Deuzq East Shinjuku 2[3] on May 20, 2019, but Luna later disputed this.
Luna was hospitalized in critical condition and remained in a coma for five days, but survived the attack and made a full recovery.
Kenji Nakano of Tokyo Reporter and Marnie O'Neill of News.com.au wrote that Takaoka's fanbase is an example of a broader and troubling online phenomenon towards attractive criminals, nearly akin to celebrity worship.
On December 5, 2019, she was sentenced to 3+1⁄2 years in prison, with the judge calling Takaoka's crime "selfish" and that she had a "strong intent to kill."