Kitty’s mother, Eve, and Principal Jina Lim appeared to be close friends according to Eve’s old albums but Jina behaves like she barely knew her in the present.
Kitty sees Jina on the first day and recognizes her from a photo in Eve’s old album but when she introduces herself, Jina pretends like she didn’t really know Eve that well before moving on.
While talking to Yuri, she mentions the fact that their mothers knew each other, and when Yuri brings this up in front of Jina, her mother says that they were roommates but doesn’t dwell on the subject too long.
Kitty finds the medical bracelet in her mother’s stuff and assumes that her mother was the one who had a child when she was there. She eventually finds out that Alex is that child, and through Alex she learns that Professor Lee is the father.
A friend in need
Kitty sends Dae her mother’s necklace on Chuseok but Yuri intercepts it and wears it herself during detention. When Jina sees it, she asks Yuri how she got her necklace and this raises many questions in Yuri and Kitty’s mind.
They go looking for the yearbook from the year their mothers were at K.I.S.S to see if they can find out more. They eventually find a yearbook in Professor Lee’s house and in that yearbook, they see a picture of Jina and Eve together.
Kitty realizes that in that picture, Jina is the one that is pregnant and must have used Eve’s name at the hospital to keep it a secret. She shares this information with Alex who eventually faces Jina to talk about it.
She tells him that Professor Lee doesn’t know about the baby and then when she goes back home to tell her husband, Yuri finally learns that she has a half brother but doesn’t find out who it is until much later.
In the end, Jina decides to tell Professor Lee and Yuri the whole truth so they can all get to know each other better as a family. When Kitty is leaving at the end of the semester, she gives her a letter that Eve had sent her but Jina never replied to.
She thanks Kitty for reminding her of how special of a friend Eve was.
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