The beginning of this MV started with a flower in a casing. The flower itself is called "Charon's Lantern". In greek mythology, Charon is the name of the ferryman in the underworld that carries souls across the river. 

Jin closed the curtain and left Jungkook in darkness. We then see the boys dancing and then the room where Jin was standing received an explosion. We can see Jin desperately trying to protect the flower incasing. However, after the hectic situation ended, we can only see sand inside of the casing with no flower left as Jin left it.

We then saw RM rapping in these containers and looking into a mirror and saw Jungkook. Then we saw Jungkook standing outside of Jhope's room where he seems to be locked inside this room filled with carnival things. Jhope seems to be trying to escape from that room, but sadly can't. 1:20 into the video where Jhope is giving up, we can see a snickers bar being slipped into the keyhole. We then can see Jimin's room where Jungkook looked down into the ventilator and saw Jimin looking up at him.

Jungkook then ran inside this door and he ran across the hallway as the floor started to crumble down. Here we can see V holding his phone and suddenly turned into sand. Jungkook then looked down at the ground as if he knew V was below him. V's room is the illuminated by these lights with the words 'save me' written on the wall behind him. We then can see Suga inside this room with the piano and the guitar. It switched a little bit to a scene where Jhope seems to be drowning in snicker bars and it went back to Jungkook and Suga. Jungkook bent down and saw Suga sitting on a chair. A fire sparked through his window and he looked to where Jungkook was looking. Then the scene changed to Jimin turning off the tap of water flowing.

Here we see Jungkook picking up the sand from the abandoned lantern. The sand then changed into flower petals and a secret door behind a waterfall opened. Jimin's room is then started to flood with the water falling down from the ventilator and Suga's room is now sparking with fire. However, neither of them moved an inch and Suga smirked. Jungkook then entered this room and went face to face with this mysterious figure from the 'Fake Love' teaser.

The song ended with all the members in shadow as a hand from 2 members held each other and one of them fell down leaving only one hand in the air.

Okay, bear with me for this theories,

So from what I see and concluded is that Jin is trying to save the other members. Remember on how I said that the flower's name is "Charon's Lantern" where Charon is the ferrymen who deliver souls in the underworld across the river of pain. So I think that the flower is a one way ticket for Jin to travel to the underworld and save the other members. Instead of him travelling to the underworld, Jin asked Jungkook to save the other members by going to the 'Magic Shop' where they can exchange their fears or sins for a positive attitude. That's why Jin tried to protect the flower even though in the end he failed to protect the flower.

Jungkook then saw all the other members on how they are trapped in the river of pain. They are burdened by their mistakes from the past. RM saw Jungkook's reflection in the mirror, Jungkook stood outside Jhope's door and gave him snickers to help him stay alive as a symbol to not give up, Jungkook looked down and saw Jimin looking up at him. At the same time in the real world Jin stood up to reveal the flower has turned into sand. This symbolized an hourglass and the amount of time Jungkook have is little.

Jungkook seems to be running away from something as the hallway breaks apart. It means his time is running out. V who is below Jungkook holds a phone that turned into sand. It symbolized how V can never tell anyone about his problems. He never had the chance to just like how he killed his father and called RM but he didn't pick up because the telephone booth was locked. The writing 'Save Me' behind V is actually the words that V is trying to say, but he couldn't tell anyone.

Then there was this scene where Suga threw his guitar out of frustration. The guitar is from the Highlight Reel, the girl who accompanied Suga at that time. It seems like Suga had some bad memories with her. Jungkook then saw Suga and he left, meanwhile Suga's room started to spark with fire and he looked at the direction where Jungkook was.

We then see Jungkook arriving to the waterfall. I do think that the waterfall is from the underworld that goes by the name of Phlegethon where in the greek mythology is a way to reach the depth of Tartarus which is Hades's house. 

We then saw Jungkook picking up the sand and and turning it into petals of flowers. Jimin's room was then filled with water, Jhope was buried with a pile of snickers bar, V looked at the writing 'Save Me',  and Suga's room was consumed by the fire.

Jungkook then met the man in the mask and the cloaked who seemed to be the 'Time Keeper' and the one who owns the 'Magic Shop'. The MV ended with two hands holding each other and the other hand dropped down.

This symbolized the 'Fake Love' Jungkook was making or I would say fake hope. Since in the end, all the members are still stuck with their sins and problems and it's getting worse. On how Jimin's room became flooded, or how Suga's room was consumed by fire. It seems that Jungkook betrayed all the members and giving them false hope that he could save them, in the end only Jungkook arrived at the magic shop by giving the lives of the other members he will receive something better. 

This is Jungkook's 'Fake Love'

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Don't hate me on this, it's just a theory chill. I'll probably make a happy ending theory later for 'Fake Love' so don't worry