Ok so as I was watching it I was trying to see if there were things that linked up and we'll these are just my thoughts. Honestly I watched it like four times. The first time I was so confused on what was going on plus them feels.
In the beginning you can hear their song Butterfly. I don't really know where I was going with that it just caught my attention. (Also I've never really done this so yeah sorry)
Honestly I have no idea what's going on but I noticed that when Jungkook and Suga were fighting tooth there intern them in the blue writing it says "look for you" I'm not sure if they maybe had like a falling out or maybe Suga was over stressed and Jungkook was trying to bring him back to his senses so he wouldn't lose himself because of what ever pain he was feeling.
When it got to this part I was quickly reminded of Jimin's part in I need u and it made think that maybe this is like an alternate universe or something and they're there to help him cheer up so it won't end up like it did in the I need u MV. Then the words on the door caught my attention too. Inhale. Exhale. Breath.
This part to me seemed like the house represents them being in like a state of limbo or numbness because of what they went through and V is the one that's like giving them a wake up call back to the "reality".
The quote on Rap Monsters jacket caught my eye because it says "There is always sunshine in my heart" too me that gives me the sense of happiness and hope and not giving up. Idk if maybe I'm just influenced by everyone else's theories that I've read or if it does mean something.
This last post made me think that in the beginning when he went down it meant that he had kind of given up. And while he was underwater it could of meant despair, worries, maybe hurt, all those negative emotions. But his friends were there trying to help him overcome it and not to lose hope and in the end he realized and that's why he came back up to the surface. Because at first you see him being calm underwater but later on it seems like he starts to regret it and starts to "fight back" that's why he starts squirming a lot.
Also when I see V underwater like this it reminds me of when he jumped from that tower thing into the water.