Synopsis: My Favorite Idol Will Be Protected by His Strongest Fiancée

"Now that I've decided to protect you, don't you dare leave my side on your own." Yoshino Nina was born into a family of bodyguards (SPs). She is the strongest young woman, gifted with natural protection instincts and combat skills. Despite her abilities, she has always admired "cute girls" more than anyone else. So she abandoned her path as an SP and works as an office lady (OL). In her free time, she enjoys being a devoted fan of Luka, a member of the wildly popular idol group "Riot." One day, Nina hears the news that Luka has gone missing. Then she gets into an accident. When she wakes up, she has been reincarnated as "Nina," a noble daughter in another world. And there, she comes face to face with someone who claims to be her fiancé — her favorite idol, Luka himself! But it seems that Luka's life is being targeted by someone. Nina volunteers to become Luka's personal bodyguard. She couldn't protect her beloved oshi (favorite idol) in her previous life, but she is determined to protect him in this world — even if the closeness with Luka makes her heart pound uncontrollably...