The boys look at him with foolish smiles as they goof around the Korean-Canadian rapper, Mark. "Shut up you boys." He says, embarrassed frustrated, using his hands to massage his throbbing head. Doyoung had thought it would be incredibly fun to buy a lie detector (the one you see in variety shows) and play it with the NCT boys during their monthly bonding time as an entire team. Taeil supported him and they both came back with that heck of a machine after seeing a shop selling it that day while they were out on schedule. They sit together in one of the practice rooms. The questions started off simple. Taeyong asked if Haechan had messed up the laundry and if Jisung had spilled the cereal in the kitchen without cleaning it up (Haechan denied and got electric shocked by the machine, proving he lied, while Jisung absentmindedly admitted and the machine made a 'ding!' sound, proving he said the truth.) Jaehyun asks Jaemin who he thinks cook better, Taeyong or him, in which Jaemin chose Taeyong ('ding!') and almost got strangled by Jaehyun. More questions were asked that resulted in the usually gentle Winwin hitting Chenle, Yuta wanting to scream at Johnny, Hansol and Ten laughing so hard they almost fell, and much more.

Then things got weird when the questions got related to... girls.

Ten asks Yuta if he would hit on Hina. "No???" The Japanese guy exclaims as he puts his hand on the lie detector, "Sure she's from Japan too but she's too young???? She's like year 2000 or something right?" He wasn't exactly directing the question to anyone but Jisung nods. "Noona." He says and Jaemin remarks, "We're same-age friends." "Exactly." Yuta says and the machine makes a 'ding!' sound to prove he's saying the truth. "You're no fun." Ten teases and Yuta looks at him, bewildered. "That's downright e if I like her?" Ten laughs anyway and Yuta adds in defense, "It's like Doyoung liking Yeri!" Surprised, Doyoung sits up and replies, "But I don't like Yeri that way???" Taeyong laughs and Doyoung just continues, obviously startled, "If anything it's this guy." He points to Jaehyun beside him. "You like him?" Yuta asks on purpose. "No, he likes Yeri!" Doyoung shout, still pointing at Jaehyun with his index finger. Jaehyun casually bends Doyoung's finger and he yells. "Oh really? You like Yeri noona?" Jisung asks innocently, eyes widened. Jaehyun remains silent and Mark laughs. "He's shy." Mark jokes. "Look who's talking." Haechan nudges Mark and he turns. "What?" The Korean-Canadian looks at him, confused. Haechan coughs and Jeno goes, "Ahh is it about Koeun noona?" Everybody immediately went "Ayee~" "I remember Herin said you're like the father and Koeun is the mother." Jaemin says with his million-dollar smile on. "Keep quiet." Mark says simply and Jaemin laughs. "You have a child?!" Haechan gasps dramatically and pretends to fall backwards in shock. Johnny starts shaking his head, pretending to be disappointed at Mark. Winwin, though still a little slow in understanding Korean, shakes his head too, making Kun laugh.

"N-no?!" Mark exclaims, "I - I didn't do anything strange!" He got very flustered. "I'm just talking about Jisung. Look he's so young. What a child." Haechan jokes, patting Jisung's head. "Yah you keep quiet, you ain't that old either." Taeil says to Haechan and pats his head. "W-why are we talking about Koeun??" Mark asks again as the guys continued looking at him strangely. "Because you like her." Hansol says. "No I don't! We were talking about Jaehyun hyung and Yeri! Why me now?" Johnny leans forward and taps Jaehyun's knee. "Jaehyun do you like Yeri?" He asks. After thinking a bit, Jaehyun shrugged and put his hand on the machine, since they were all ganging up on Mark, he answers, "To be honest, please don't tell her, but yes. When I first came into SM for a few months I really really liked her? Now not really, sometimes a little, mostly no, because I just debutted and I don't see her often." The machine made a 'ding!' sound and everyone "aye~~" again but Jaehyun now shoots Mark the question, "See I answered, so do you like Koeun?" "I - I don't!" Mark says as the machine is pushed towards him and Johnny forces his hand onto it. "Say it again." Doyoung tells him and Mark repeats, "I don't like... Koeun that way." A few seconds later it's basically a screaming Mark and all the boys collapsing with laughter. The machine electric shocked him. He lied. Mark tries to explain. "It's only like this because I was flustered when you asked me the question!" He shouts but no one believed. Usually confused and lost baby chick Jisung giggles along too. "Mark - Koeun." Ten says. "Shut up." Mark replies. "Rude." Ten snaps his fingers. "But you're close right?" Taeyong asks. "We're the same age." Mark replies. "But Yeri is the same age." Yuta adds, "And you're not that close to her." "I'm okay with Yeri!" Mark tries to defend himself. "I saw her on TV the other day," Kun says, "It was a show, I forgot the name but Red Velvet was there and Yeri was asked to rank her top 5 closest NCT friends." All ears on Kun now. Kun continues, "She said Jaehyun first, Haechan second, Mark third, Jaemin fourth and Taeyong fifth." "See," Hansol says, "You lost to Jaehyun who's 2 years older and Haechan who's a year younger. So you're not exactly close to everyone who's the same age!"

Mark facepalms himself. "I er talk to Koeun more." "And why?" Doyoung asks more. "Because we filmed Mickey Mouse Club together and are the same age!" He answers. "But you talk to Koeun alot before that already." Haechan says. "Would you SHHHH for once?" Mark says, covering Haechan's mouth. Then out of nowhere, Jisung goes, "Koeun noona is pretty." Everyone starts agreeing except Mark. "No she's ugly have you see her derp?" Mark asks. "No of course not." Ten replies, "Because we don't talk to her as much as you do." Kun is still laughing as Mark starts to run his hand through his hair. "I walked pass the girls' training room a few days ago and they were dancing to 'Sorry Sorry' and the part Mark covered was also covered by Koeun eomma." Haechan says and Mark is about to choke the guy. Jaemin laughs as Jisung adds, "We're all her kids." "Who?" Taeyong asks and Jisung replies, "Jaemin, Haechan, Jeno, Herin, Hina and Lami we're all Mark hyung and Koeun noona's kids." Everyone holler and scream and laugh obnoxiously as the Korean-Canadian throws a pillow at the young kid. "Don't talk nonsense." He mutters. "But you're always having skinship with her!" Jeno adds fuel to the fire. "Kids you all are too young." Jaehyun laughs. "Yeri is too young." Taeyong tells him and Jaehyun pushes him away. "So do you like her or not?" Doyoung asks Mark. "Koeun..." Mark mutters and then messes his hair up in frustration. "So??" Haechan pesters him and Taeil gives him a curious look. Silence feels the room as they all wait for him to answer.

"... Sort of?" He says, eyebrows raising cautiously. The boys scream and a few of them start running around the room. Mark immediately tried to get everyone in control, shushing them because everyone is so loud it's crazy and it's scary because he just told a secret he kept hidden for so long to this bunch of wild guys. And mind you, that's 17 guys. A few more minutes of extreme screaming and teasing and whatnot when suddenly their practice room door flings open. A few boys realised. They stop and stare while the rest continued their nonsense. Mark had his back facing the door as he tries to pin a teasing Ten and Jeno down onto the floor. Haechan hits his back a few times. "Yah yah yah... eomma is here." He whispers and Mark ignored him at first but then stops when he realises. He gets up and turns around, seeing an arms-crossed unamused Koeun standing at the door with a tired and also unamused Hina behind her. By then everyone had quieten down. "These dance studios ain't that sound proof right? It also doesn't help that there's almost 20 of you shouting at the top of your voices. You have the energy so you want to play and kill each other, that's great for you, congratulations. But we're tired and we have to practice, evaluation is coming up soon. It's not easy so please co-operate." Koeun says, direct and straight-forward as usual, running her hands through her hair, messing up her bangs a little but they fall back into place almost immediately. Hina's sigh is incredibly audible as all 17 NCT boys kept silent after Koeun's words. The Japanese girl shakes her head a little and walks away without saying anything just as Herin pops up from the back looking gloomy. Koeun sighs too as Herin puts her chin on her shoulder and starts to speak again, "I know this sounds rude and everything because after all you guys are sunbaes but we couldn't even hear the music and had to shout to hear each other and it's very frustrating for us..." Sweat is still dripping and Koeun looks so tired Mark was frowning in concern. He stares at her but she doesn't make eye contact with him. Herin walks away after a girl's voice is heard calling for her from behind. "We're fatigued and we haven't eaten for hours and I really don't want to waste energy on this but please." Koeun says one last time and adds, "And I'm sorry. Have a good evening." She finishes and bows, closing the door behind her. "Mark I think you should go after her." Johnny tells him, not in a teasing way but in a genuinely concerned way. "Go go." Jaehyun says, a little taken aback from that and pushes Mark. He walks over to the door too and looks at the boys, "E-er... I'll be back." He says and exits. "Gosh I feel so bad..." Haechan says, still shocked from Koeun's entrance just now. "Eomma is tired." Jisung says quietly.

Mark steps into the corridor and notices the dance studio right beside. He hadn't knew they were in there and it's right beside them. No wonder they complained. He knocked politely - they wouldn't hear it but anyway - and opened the door carefully, poking his head in. Lami happened to be sitting on the floor beside the door and flinched when she saw him. "Sorry." He muttered, apologising for scaring her, "Is Koeun here?" As Lami shook her head, Mark hears a voice from behind him, at the corridor. "Looking for me?" A girl says and he turns. It's Koeun. He smiles. "Yeah." He replies. "Why?" Koeun asks, managing a smile back to him as she gestures him to open the door wider for her to enter. He notices her carrying a few cans of coffee and energy drinks and pushes the door for her to enter. He follows her inside the studio and watches her put the drinks down. "Girls, take a 10 minutes break!" Koeun shouts after settling the drinks down and going to turn off the music. "You wanted to talk to me right?" Koeun asks the silent Mark who has just been following her around in the studio.