Hanyeo

Kang Ha-Na, a former girl group trainee, gives up everything and has a baby due to an unexpected pregnancy. She leaves the baby in a baby box until she can save up for a house deposit, but she finds out that a famous actor and director couple have adopted the baby, and she goes to work as their babysitter to get the baby back. However, the wife, Angela, is transfusing the baby's blood. Like a vampire. Kang Ha-Na decides to kill her.

(Source: Naver, translated)

Note: Part of YLAB's Red String Universe.