When you live and work with someone for the majority of your career, fights are likely to ensue once in awhile. Most idols tend to keep it under wraps, but these fights within members are well-known amongst fans.

1. SHINee's Key and Minho

During an episode of "Happy Together", Minho and Key revealed that the two didn't like each other as trainees. Minho had joined the company first, so he considered himself Key's senior despite being the same age.

One day, Minho asked Key to clean something up, but the latter didn't take kindly to being ordered around and spoke back in dialect. He had meant to say, "Are you out of your mind?" but ended up saying, "Did you eat a stone?", which meant the same thing in his dialect. Minho tried to tell him why he should clean up, but Key said that the two were equals who signed the same contract and that he can clean up himself. Key admitted he didn't know the hierarchy at the time.

Following the fight, the two remained awkward for three years after the incident and only became close after their debut.

2. Super Junior's Ryeowook and Siwon

On an episode of "Radio Star", Super Junior revealed that Ryeowook had fought with Siwon... over high fives! Apparently, Siwon would constantly ask for high-fives and Ryeowook was sick of it, so he told him to stop, even asking if it was so necessary to high-five every day. Siwon then asked him if he was confident enough to never see him again, to which Ryeowook replied that he is confident. Siwon then admitted the two don't match well due to their different tastes and styles. In the end, the two signed a contract that would limit Siwon to three high-fives a day!

3. BTS's J-Hope and Jungkook

J-Hope and Jungkook had fought early in their careers. Jungkook had received a fruit basket from a fan, which he really treasured since at the time, he didn't have a lot of fans and never received a gift from a fan before. Since there were a lot of fruits, he told his members to have some. However, he noticed that the fruits were running out quickly, had wanted them to slow down so that he can savor the gift he received. He had noticed J-Hope was going to eat a banana and had asked him if he could not eat. J-Hope got annoyed at him and threw the banana at him, then said, "Whatever, eat it you b*st*d."

J-Hope had found Jungkook annoying and selfish. At the time, all the members were eating fruit from the basket, but Jungkook had only called out J-Hope, which led him to feel called out and isolated. Jungkook, on the other hand, just wanted to savor his gift. Jungkook claimed it was the angriest he's ever seen J-Hope.

4. NCT's Mark and Haechan

This fight may be the most ambiguous on the list because no one knows the real reason as to why the two had started fighting. Many note that it started in 2017 during NCT 127's "Cherry Bomb" era and bled into NCT Dream's "We Young" era.

On "NCT Night-Night", Jaehyun mentioned that Mark and Haechan, who were previously roommates, had been fighting almost every night. Their fights were so loud, you could hear it through the walls. The fighting between the two had gotten so bad, Mark switched rooms with Doyoung to get away from Haechan.

Fans also noticed airport photos of the NCT Dream members as they were preparing for their "We Young" comeback, and Mark and Haechan looked noticeably upset in their photos. Their anger with one another persisted throughout the promotions, and it was noticeable. During the original choreography of "We Young", Haechan should put his hand on Mark's shoulder. They had performed that move or the earlier stages, but fans noticed that in the later stages, the choreography was changed so that they would no longer need to touch. In a Jeno fancam, fans spotted the two in what seemed to be an argument.

The two ended making up in October and have since performed the original choreography of the dance. After the fight, Haechan revealed that Mark had changed his name on his phone from "Beloved Donghyuck" to "Hateful Donghyuck", so he changed Mark's name on his phone to "Hateful Mark".

5. MAMAMOO's Moonbyul and Solar

During an episode of "Life Bar", the two MAMAMOO members revealed they didn't like each other when they first met. Their first time to meet was at an evaluation at their company, and Moonbyul had forgotten to bring heels that were needed. Solar decided to lend her some heels. When the staff had asked Moonbyul where she got her heels, Moonbyul pointed at Solar and spoked informally despite Solar being older. Solar became frustrated at Moonbyul for her attitude, but Moonbyul revealed that she really through Solar was younger because she looked young. Solar's anger melted when she heard that.

Moonbyul revealed she didn't like Solar at first because when the staff took photos of them and told them to act like good friends, Solar hugged Moonbyul from behind. Since it was the first time they met, she thought the sudden skinship was too much and found her weird.

Though the two are now close, they still fight often. Solar revealed that when they fight, they don't use words; they fight with their fists! Moonbyul also revealed the two often fight over small things, and they fight immediately instead of letting it get worse.

6. BTS's Jin and V

A part of BTS's documentary film "Burn The Stage" showed an argument between members Ji and V ten minutes before a concert. V was telling Jin that he had to be faster in their choreography to get to his position. Jin said that he ran as fast as he could and that he couldn't do anything about it, which led V to get angry saying he had to be faster since he takes too long to get ready. Jin starts asking V to take smaller strides, to which V said he would if Jin would be faster. V was getting frustrated at Jin saying he was doing his best and going as fast as he can. However, Jin claims that if he goes any faster, he will lose the tempo.

The members voiced out that none of them were right in this situation, with member RM saying that they cannot fight before a concert. Jin, as the hyung, decided to apologize first and acknowledged that he should have taken him more seriously. The two realized it was not a big deal, and V ended up shedding tears after the fight.

After the concert, the members all talked about it and pointed out that both sides were at fault. They soon left Jin and V to talk about it and come to a resolution alone. Both members ended up apologizing to one another and promised to be better.

7. EXO's Lay and Baekhyun

During an episode of "Star Show 360", Baekhyun revealed that as a trainee, he decided to watch Lay practicing dancing, as he was aware that the latter was an amazing dancer. However, Lay was bothered that Baekhyun was in the practice room and not practicing, because he hated when people slack off. Thinking Baekhyun was lazy by just watching him, he asked Baekhyun if he would be practicing. When Baekhyun revealed he wasn't, he asked him to leave: thus, the infamous "nagajuseyo" meme was born. Baekhyun felt shocked by being asked to leave and ended up feeling awkward.

8. DAY6's Young K and Jae

During an appearance on "Super Junior Kiss The Radio", Young K opened up about a time where he and Jae hated each other more than others in the team. At the time, Young K was DAY6's guitarist, but his position was switched to bassist and Jae as guitarist following the latter's appearance on "K-Pop Star". He explicitly said, "Hyung came last and took my guitar away". However, he hinted that there are more reasons, but did not go into detail.

Now, however, they are the two closest members, and the two even share a room in their dormitory!

9. TWICE's Sana and Dahyun

(Photo : YouTube)

During an episode of "SIXTEEN", the survival show that formed TWICE, Sana and Dahyun were in a group, along with Tzuyu and former JYP Entertainment trainee Minyoung. Following a rehearsal in which the girls were scolded for their lack of cohesiveness and teamwork, the girls scheduled a rehearsal to fix the problems mentioned. However, only Tzuyu and Sana showed up to the rehearsal on time, which led Sana to become frustrated. When the other two members showed up late, Sana lost her cool. As Dahyun tried to apologize, Sana said, "Honestly? I don't want to hear your apologies. [...] Did you think I was joking? I'm totally serious."

The two later made amends in a team meeting, with Dahyun tearfully apologizing for not taking practice seriously. Sana apologized for losing her cool, and the two became stronger than ever.