Tong yao a 20 year old girl who holds many secrets and a tragic past No one knows her secret not even her mom After losing her father at the age of 7 her mother send away , to her aunt's house in London After 1 year her aunt and aunts son started abusing her at the age of 10 she ran away from her aunt's house From the age of 10 she works 2 part time job to earn money And she studied from scholarship When she turned 14 she got into street fight and illigal bike race for money where she met Cha Eunwoo he was 5 years older than her , they grow closer and become a family, few months later they join a mafia group because they were young but strong and no one will suspect them , but they got to know that they do illigal business so they both left the job At the age of 16 she entered university due to high iq The boy and got into the same University Where she met 3 girls , ??? ??? ??? They all made their own mafia group Xiao, also tell them about her past and everything, they also started to hate her mother While her mom moved to her mom's hometown Seoul , she adopted a girl named, Ara , a total slut , fuckgirl , Playgirl, bitch , gold digger and a money minded girl What will happen when xiao find out that her mother fall in love with a mafia king and she is having 11 step siblings and a adopted girl What will happen when she meets her old friends who she thought they are dead Based on Falling into your smile character's