After the loss of a loved one, Jisu is offered a helping hand from her late grandmother’s student, who provides her with a place to stay and takes her under her wing. Despite her wish to get along, Jisu gets off on the wrong foot with their only son, Hajin, who mistakes her for a stalker after he encounters her on his doorstep. Will Jisu be able to resolve this misunderstanding and befriend Hajin? Or will their relationship turn into something more?