For centuries, the deadly arts have been perfected by Masters, and Five Great Families hold the greatest power and influence. Hikaru Gero, an heir to the Gero family, lives in the underworld as an elite assassin. When his sister is pressured to produce an heir, Hikaru asks Mei Kinosaki, a brilliant marriage swindler, to find him a bride. The most challenging mission of his life begins!

Pessimistic high school student Hana Tabata doesn't believe her life could ever be like that of a heroine from the shoujo manga she reads—she's convinced she's ugly, and she's always alone. Still, she can't help but imagine herself as a leading lady when she's changing out flowers early one morning...until she's caught in the act by her handsome classmate Yousuke Ueno! Hana can't wrap her head around his kind words at first, but as they grow closer, she finds her life slowly beginning to change…