Two Sisters and Two Brothers / Runaway Sisters, Marry Brothers? / Accidentally In-Laws / Run, Sister!

Zhou Shengsheng is on the run with her sister Zhou Anning to escape an abusive man, when they encounter mercenary Mo Xiao and his brother Mo Xing. Shengsheng has a one-night stand with Xiao and gets pregnant. She intends to get an abortion, but Xiao proposes marriage, taking both sisters into his home. Living under the same roof, Shengsheng gradually wins Xiao's heart, while Xing falls for Anning. Through a series of events including a jewelry store robbery, prenatal classes, and confronting the abusive man, the two couples find their happily ever after.