To Love Our Enemies summary:

"No matter what kinds of challenges I will face, I must overcome it." The smiling bright girl, Goo Eun Sae. Ever since she was little, she was raised in an orphanage. Because she is the number one student of the entire nation, she was chosen by the chairman of a rich company to help his son be the top ten students of his school. In turn, the chairman will send money to Eun Sae's orphanage to help the kids. No big deal right? However... "My god! The chairman's son is in 400th place of the entire school?! How can I help him raise up into top ten in only one year?!" Can the bright girl, Goo Eun Sae do it? For the children's sake she must try her best. But what kind of person is the chairman's son? How many more hardships will Eun Sae face? Will her smiling, innocent face like sunshine shed painful tears? Will love bloom out of this?