Kim So-eun has gained popularity by her acting in Boys Before Flower as Geum Jan-di only best friend, Chu Ga-eul.

Now, people are starting to recognize Shin HyunBeen more through her acting as Jang Gyeo-ul in Hospital Playlist.

Both have season name; Autumn and Winter.

They both have a big crush to someone in each drama.

Ga-eul to Seo Yi-jeong, played by Kim Bum.
Gyeo-ul to Ahn Jeongwon, played by Yoo Yeonseok.

Both Kim Bum & Yoo Yeonseok are from the same agency; KingKong by StarShip (formerly known as KingKong Ent.)

From each drama, they have their own official couple name (named by fans).

Seo Yi-jeong & Chu Ga-eul= SeoEul couple
Jang Gyeoul & Ahn Jeongwon = GyeolJeong (Winter Garden)

Since the viewers were rooting for SeoEul couple, many of them wanted both to have their own drama or officially dating in real life, since Kim Bum and Kim So-eun are classmates at ChungAng Uni.

(I remember that most of So*mpi users were also shipping them hard)

But, instead of getting their own drama, Kim Bum and Kim So-eun have been recruited to be in several project and CF. They both casted as a couple for Bonjuk and Samsung Anycall Bodyguard.

And the dynamic about this thread is, maybe sooner or later we could get any projects related to Shin HyunBeen and Yoo Yeonseok.

I know, I'm trying to connect the dots between them. But...

We have like several products now to get advertise by them, Levi's denim, Chocopie, what else?

Maybe they can endorse "how to not repressed your feeling when you're a doctor" kind of insurance advertisement

To add:

Kim So-eun was a former Fantagio actress, as well as Jung Kyungho, they signed to the company at the same year.

They both appeared on the same project called After School Bokbulbok (a webtoon drama, to introduce 5urprise) as a pharmacist.

Shin HyunBeen almost got to work together in One More Happy Ending with Jung Kyungho, before Hospital Playlist happened.

To add:

Chu Ga-eul wasn't the character who fall in love at the first sight, because her character knew hat Yi-jeong sunbae was a playboy, so she tried to avoid him.

But Jang Gyeoul admitted to Lee Ikjun that she fell in love with Ahn Jeongwon from the first time they met.

When Ga-eul recognized her feelings, she pursued her love to Yi-jeong since he can't forget his first love yet, to the point she gave up.

When Gyeoul learned that Gyeoul was lying about Yangpyeong, she told Ikjun that she needs to give up trying.

Both characters are fierce

Remember Ahn Jeongwon's hobbies during four seasons?
In winter, he likes to go snowboarding, right?

It reminds me of something...

I don't know if this is true, but I do think that Shin HyunBeen is more like a cat person than a dog person. And it happened that Kim So-eun is known as a cat person, her cat name Cuni

Too add:

Kim Bum's character in BBF was a rich high school playboy who resent hi father. He even rudely offer his father to date Ga-eul one time.

Yeonseok's character in HP is a virgin who wanted to be a priest, warm, and an emphatic person, but only being cold to one woman.

Although being in the same major, Kim SoEun stated that she became awkward with Kim Bum when people starting to ship them in real life.

Shin HyunBeen clearly draws the line when she was asked about Yoo Yeonseok in another perspective in life. She refers him to be just a sunbae.

To add:

Both Chu Ga-eul and Jang Gyeo-ul character's personality was a straightforward kind of person. They will tell you right away when something wasn't feel any right.

To add:

Chu Ga-eul was the only daughter in BBF.
Jang Gyeoul does have a brother, I think that she's the oldest of two in HP.

To add:

Yi-jeong was the only person in F4 who called Ga-eul with the honorific -yang. -yang is used in formal occasions such as weddings.

Meanwhile Jeongwon keep using formal language to Gyeoul for 10 episodes in HP, until he using banmal in the end of episode 10.

Another trivia about the two:

Both also have been working together with Shim ChangMin (DBSK).

Shin HyunBeen & Changmin: Mimi
Kim SoEun & ChangMin: The Scholar Who Walks the Night.

I REALLY LOVE TO TORTURE MYSELF, but here's come the math:

Shin HyunBeen: April 10th
Yoo YeonSeok: April 11th

Kim SoEun: September 6th
Kim Bum: July 7th

Both couple birthday were separated by one number, and the women both were on the lead... I'M CRYING NOW!