Yumi's Cells

After breaking up with Woong, Yu-mi struggles to move on while her cells fight to keep her life together. Ba-bi comforts Yu-mi, who tries to hide her pain. Before long, her Cell Village secretly forms a Yoo Ba-bi fan club.

Ba-bi's unexpected confession leaves Yu-mi flustered, while her confidence soars. Unaware of Yu-mi's growing feelings for Ba-bi, Ruby enthusiastically tries to set Ba-bi up on a blind date.

Devastated by news of Ba-bi's blind date, Yu-mi hopes he won't go but can't bring herself to say it. She spends the day worrying, and a message arrives just as she dozes off.

Yu-mi and Ba-bi begin a sweet romance that changes her life. A visit to a book café rekindles her long-forgotten dream of becoming a writer, and someone keeps encouraging her to pursue it.

Yu-mi unexpectedly reunites with Woong through a secondhand sale. While Woong sees it as fate, Yu-mi is torn by old memories. A message from Woong arrives as Yu-mi prepares for Christmas with Ba-bi.

Yu-mi pursues dream of becoming a writer. A cozy date at home with Ba-bi gets interrupted by Yu-mi's parents, who arrive without warning. Things quickly grow awkward as her father openly sizes Ba-bi up.

After repeated writing contest rejections, Yu-mi begins doubting her talent despite her determination. Just then, she receives an unexpected offer to return to Daehan Noodles.

Da-eun, an intern at Daehan Noodles' Jeju branch, gives up on Ba-bi after learning about Yu-mi. Meanwhile, publisher Ahn Dae-yong is stunned to discover his promising new writer is his college first love.

Working with the eccentric illustrator Control Z pushes Yu-mi's patience to its limit. Later, she visits Jeju to spend New Year's with Ba-bi, only to learn he put his house up for sale.

After breaking up with Ba-bi, Yu-mi's Writer Cell becomes her Prime Cell, massively improving her writing. Meanwhile, the now-successful Woong is surprised to learn Yu-mi is an author and that Control Z is her illustrator.

Hearing Ba-bi has returned to Seoul, Yu-mi tries to avoid him but runs into him at his favorite café. After imagining this moment countless times, Ba-bi finally stops her to speak.

Tension between Woong and Ba-bi escalates and Yu-mi finds herself caught between them. While planning Ba-bi's birthday, she learns he's leaving for the U.S., making their second chance at love even harder.

After Ba-bi proposes, Yu-mi meets his father and does everything she can to make a good impression. Meanwhile, upon hearing of the wedding, Woong asks to see her one last time.

On her wedding day, Yu-mi panics after losing the laptop containing her unfinished manuscript. As she desperately searches for it, an unexpected person calls to say they've found it.