Jeon Wonwoo and Kang Seulgi first met when their two groups appeared on the variety show Running Man. The two were settled in a team together with Lee Kwangsoo and after that one-day filming, Wonwoo and Seulgi became really good, close friends.

During Running Man

"Who's older between you two?" Kwangsoo asked as he drove towards the first mission site, Seulgi and Wonwoo in the car with him.

"Seulgi Noona," Wonwoo answered, who was seated at the passenger seat.

"Really? Wow, that's amazing, Seulgi you look so young," Kwangsoo commented. "How old are you?"

"I was born in nineteen ninety-four. "Seulgi said. "Wonwoo is two years younger than me I think, right?" She looked at Wonwoo.

"Yeah, you're correct," Wonwoo nodded his head.

"Ahh, I see... your voice is so deep and manly, Wonwoo, it's really manly," Kwangsoo commented, being his real self at meeting new people, always amused at things he didn't know.

"Ah, thank you," Wonwoo laughed.

"Seulgi, you have an amazing voice too, you two should do a duet together, like the song A Midsummer's Night Sweetness. Wonwoo's really good at rapping, Seulgi you have nice vocals, hold on, let me put it on,"

"Oppa, it's okay," Seulgi said quickly, she wasn't ready.

"I wan to hear you guys sing this," Kwangsoo said. "Okay, go," the music vocals of Raina started and Seulgi also started singing, starting a bit hastily but she got the flow soon, not wanting to be rude. Wonwoo suppressed his short laugh as it had really flustered Seulgi, and when San E's part came, he rapped as well, he was quite experienced with the song since he had sang it live with lablemate Raina before.

"Oooh, you guys are good, really good," Kwangsoo said and smiled while clapping his hands when the song ended. Seulgi and Wonwoo turned to look at each other and laughed. 'Well that went well,' Seulgi thought. 'Maybe we should do a duet.'

-

"Wonwoo, I can't do this, this is crazy!" Seulgi said aloud and gulped. The mission was to bungee jump or climb a series of stairs to get a hint for the final mission and they had picked bungee jump since it was quicker but Seulgi quickly regretted the idea of agreeing to Kwangsoo's choice to bungee jump from the highest in Korea.

"We can do this Noona," Wonwoo said, looking at her with determination. "Just close your eyes, it should work, I'll reach for the card," and it was two out of the three members who had to do it, Kwangsoo gave Wonwoo and Seulgi the offer since it was their first time on Running Man and the first time to bungee jump.

"Noooooo," Seulgi half-whines, half laughed, Wonwoo couldn't help but laugh as well. Seulgi took a deep breath. "Okay, I can do this," she told herself with courage before putting her arms around Wonwoo, he did the same, tightly hugging her body.

"Noona, are you ready?" Seulgi shook her head, a short laugh left Wonwoo's mouth. "Okay, one, two three!" Wonwoo counted loudly and they jumped off the platform. Seulgi's high pitched scream could be heard clearly and Wonwoo who had an amused smile on his face the whole time, grabbed the piece of card with his hand and put his arm back around Seulgi as soon as possible. "I've got the card," Wonwoo breathed out and he could feel Seulgi had relaxed. "Wasn't so bad was it?" he laughed.

"Wasn't so bad? It was the worst!" Seulgi said an lightly punched his shoulder, laughing a little. From there, they could hear the cheering and clapping of other members who picked the choice to bungee jump, which wasn't much but Jihyo's team was there for sure, with two other members from SEVENTEEN, Dokyeom and Seungkwan, the two jokesters of the group.

-

After that of filming, Seulgi and Wonwoo exchanged phone numbers and got close with each other, media always catching them two having drinks with each other, so many times that rumors started spreading that they were dating speculated around and both the companies denied the rumors and said that they were just very close friends.

And after those reports, Kang Seulgi and Jeon Wonwoo were appointed MCs for MusicBank, and they emceed the music show very comfortably, and right before they did that, the two performed A Midsummer's Night Sweetness together on stage and was loved by many fans, but there were still some fans who didn't like their close relationship, particularly Wonwoo's fans, fortunately , they were only a very small amount of people.

"Wonwoo, come here for a sec," Seulgi said and waved a hand at Wonwoo to go to her. They were in the backstage room having their make-up done, Wonwoo just had to apply eyeliner and was then reading his cards. He looked up from his cards and walked upto Seulgi who was sitting on the chair, her make-up just being done.  "Bend down so that our faces are side by side," Wonwoo did as told and he looked at Seulgi from the mirror.

"What is it that you're trying to show me?" Wonwoo said blankly.

Seulgi laughed. "Look closely, at my face then your face," Seulgi told him seriously. Wonwoo's face turned to confusion but nevertheless looked closely at his face then at Seulgi's facial features.

"Noona, you're pretty and I have a y stoic face?" Wonwoo said, controlling his laughter and got a smack on the head from Seulgi. "Sorry, sorry," his laughed escaped. "Okay, what is it?" Wonwoo looked at Seulgi, a smile lingering on his face.

"Don't you see the resemblance?" Wonwoo made a weird face. "Our eyes! It's so the same!" Seulgi grabbed his chin and pulled it sideways so that it was closer to her face. "It's so uncanny!" Wonwoo looked at his eyes then looked at Seulgi's eyes.

The boy's face brightened with a fascinated smile. "You're right! They're both like Kim Woo Bin Sunbaenim's eyes," he said and Seulgi let go of his chin. "Are we long lost siblings, Noona?" he said, feigning dramatic tone, Seulgi chuckled and she took a crying expression selfie with Wonwoo before going on stage, posting the photo on her SNS, the description said" I just found my long lost sibling, Jeon Wonwoo! Getting many comments and likes on the photo.

-

"Do your fans really say that you look y when you have a bored or blank expression on your face?" Seulgi asked Wonwoo, they were at a  small coffee shop, Wonwoo nodded with a smug look on his face. "Prove it," she said and Wonwoo immediately pokered his face, looking right at Seulgi, she clapped her hands while laughing. "Alright, alright, y alright," she said and Wonwoo grinned before he wiped a stain off Seulgi's cheek casually. Then, both of them heard rapid clicks of cameras. "Did they follow us here?" Seulgi quietly whispered to Wonwoo.

"I don't think so, I didn't see anybody else coming in after us," Wonwoo replied. "It should be okay, we're just close friends anyway," Seulgi tried her hardest to hide her hurt expression, she did have a liking towards Wonwoo, age was just a number wasn't it?

"True.... are you preparing for a new album, your group?" Seulgi asked.

"Yeah, Jihoon has been writing and composing songs these days, as well as the other members, so yeah, maybe we'll make a comeback soon," Wonwoo shrugged. "I've been writing as well," what Seulgi admired the most about Wonwoo's personality was how chill the type of person he was, she really liked that about him, as well as his great, handsome looks. "What about yo