One morning, Sister Lily receives a letter from her twin sister -- only to be shocked by its contents.
Apparently, her sister is dating a member of the royal family...
Worried that her kind sister might have been deceived by a scoundrel posing as royalty, Lily frets but, timid and having never left town, she can't bring herself to do anything.

Then one day, the kingdom's Second Knight Order comes to the city.
She hears that the Third Prince, Liberio, is serving with them...
"This is my chance!" Summoning her courage, Lily attempts to approach him--only to be mistaken for someone else by a brothel madam, who takes a liking to her and presents her to Liberio as a prostitute----... !?

Meanwhile, as Lily is caught up in some erotic mishaps, a suspicious scheme is brewing behind the scenes----...