Kaede Shiranui An assassin from Japan. A modern-day kunoichi dedicated to her mission. A descendant of a ninja clan belonging to a government-controlled intelligence agency. Black hair in a side ponytail. Heat Resistance: ★★★★☆ Art of Spiritual Concentration Seduction: ★☆☆☆☆ In practice, she gets stiff as a board. A pure-hearted girl who hits her limit and self-destructs with a bright red face the moment her skin is praised; the situation of wearing only a towel is embarrassing enough for her.

Lin Feifei An assassin from China. She has completely mastered herbal medicine, Oriental medicine, and breathing techniques. Ends her sentences with stereotypical quirks like "-aru" or "-ne." Black hair in twin buns. Heat Resistance: ★★★☆☆ Reduces heat through breathing techniques Seduction: ★★★★☆ Expert at seductive attacks, stimulating pressure points from an exquisite distance. Usually calm, but loses her composure instantly if an unexpected accident ruins her calculations.

Charlotte Windsor An assassin from the United Kingdom. An elite spy who values discipline and tradition. She is indignant at such an indecent method of settlement as a "Sauna Battle." Platinum blonde short bob. Heat Resistance: ★☆☆☆☆ Pure patience and grit Seduction: ☆☆☆☆☆ Attempts at sexiness turn into awkward slapstick comedy. She turns red like a boiled octopus just by being stared at from close range and panics if her towel looks like it might slip.

Anastasia Petrova An assassin from Russia. A steel-walled female spy raised in harsh environments. She keeps a cool face as if the sauna's heat is actually pleasant. Long silver hair tied into a single thick braid. Heat Resistance: ★★★★★ The sauna heat is actually comfortable. Seduction: ☆☆☆☆☆ An iron mental state that remains unmoved no matter how much she is provoked. A cold endurance type who dismisses her towel slipping or becoming transparent as a "necessary cost" for the mission.

Alice Sterling An assassin from the United States. A CIA agent with a stunning physique. She has ruined many men with her natural brightness and sex appeal. Long blonde hair with a pink-beige gradient at the tips. Heat Resistance: ★★☆☆☆ Used to the heat, being from California. Seduction: ★★★★★ A style that flaunts her incredible body while using verbal seduction. Her explosive power in the early stages is unmatched, but she becomes suddenly weak when someone starts hitting on her for real.