At first, Agatha was just one of Sophie's Good Deeds. Then, they grew to love each other and became the best of friends. This friendship was challenged, however when Sophie believed her true love was Rafal. After the Old-New war, Sophie became friends with Agatha again and promised to visit her and Tedros as much as she could.
In the first book, Sophie fell in love (she THINK this, but is not true.) for Tedros