In the two weeks that the platoon has spent at the boot camp, they have gotten to know each other better. Seolhyun is not an exclusion. 
First, the platoon finds out that she is very thorough. Their lieutenant has to know where every single one of them is at any given minute — and never complains, if there is a need to save an idol from soldier fans asking for a selfie, speed up mini-interviews, or see the idols out, when they leave the boot camp for their schedules. Their senior also checks their barracks every day for cleanliness — and she checks every corner, never minding the dust under the bunks, the height of their wardrobe or the ever-present chaos in the luggage room.
Then the platoon gets to know Seolhyun’s infamous trait: her brutal honesty. Every morning Seolhyun calmly states that Sowon’s (and her slowpoke friends’) turtle pace is the lowest running speed an idol had ever showed in the history of the show. When the camera crew, filming the idol barracks tour, asks her why there is an empty bunk next to Seolhyun’s, their lieutenant simply says, «I’m their senior. They are shy to sleep right next to me. It’s very considerate of them, really. In a way». 
When Jisoo gets a food poisoning, Seolhyun, after personally seeing her to the infirmary, mentions the problem to captain Baek and, at the same time, discloses the reason of Jisoo’s condition to the camera crew, with enough details. This turns to be enough for the showrunners and officers in charge to check the soldiers' hygiene and the kitchen's sanitation and start assigning the idols to the kitchen duty — everything to prevent a scandal. (The information still gets leaked; the Blinks swear to show up and set the boot camp on fire. Jisoo, however, enjoys her three-day rest and posts a selfie with a nurse to calm her fans down. After getting well, she gushes to Nayeon about Seolhyun and the pretty and flirtatious nurse for a whole week.)
The third thing the platoon learns about Seolhyun is that, despite the honesty, she is a woman of few words. When Jisoo sweetly thanks her for her actions, she shrugs it off and says it was her duty. When Siyeon and Seunghee boast about their significant others, she keeps mum and doesn’t order them to keep quiet. When Heehyun and both Nayoungs help her with checking the cleanliness, neither does she ask them why they are doing it, nor does she explain her own reasoning. 
When Jooeun strikes all 9’s at the shooting range one day, Seolhyun comments with a restrained, «Very good». However, the very same day, after the ‘lights-out’, she sneaks her carrier in their room and opens it for everyone to see: turns out, it’s full of snacks. The platoon enthusiastically celebrates Jooeun’s success — and her belated birthday — until 2:00.
This sends them a message: Seolhyun is not only their reserved, borderline detached, appointed lieutenant, lauding the best soldiers, but also a sunbae, caring enough to cheer her hoobaes up. No wonder they are killing it at foot drill on the parade ground the next day.

***

«Atten-TION!» barks Seolhyun. «Okay, platoon, now’s the drill time. Forward, march!»
They are marching in the 30ºC degree heat. The noon sun is scorching hot; the humidity is making them all sweat — very unladylike and un-idol-like. Nayeon has never thought she would miss wearing short shorts, but here she is.
«Right flank, march!»
Nayeon tries not to have flashbacks to summer festivals; when the clothes she put on to cover herself from the sun alm