Chlorine is a chemical element that appears between fluorine and bromine in the periodic table. It is a toxic greenish-yellow gas at room temperature, which has a strong smell like bleach. Drinking chlorine would kill you and at first this is what it seems Tyler Joseph is singing about on this menacing slow burner.
Sippin' on straight chlorine
However, as the song develops, it becomes clear it is more about Tyler purifying himself of his dark interior:
This beat is a chemical, beat is a chemical When I leave, don't save my seat I'll be back when it's all complete The moment is medical, moment is medical
Chlorine is a purifying chemical and Tyler is drinking it to cleanse himself from the black thoughts inside him.
During the third verse, Tyler talks about how while his songwriting is very cathartic for him, if he over-relies on it, making music can be harmful to his mental health. Now that it's his main source of income ("double as a paper maker"), it gives him a bad taste.
Now different lives I lead, my body lives on lead The last two lines may read incorrect until said The lead is terrible in flavor But now you double as a paper maker I despise you sometimes, I love to hate the fight
The lead is synonymous with a pencil, which is of course is a writing tool.
The song's music video sees Twenty One Pilots move away from the three-part dystopian narrative series played out in their previous clips for "Jumpsuit," "Nico And The Niners" and "Levitate." This visual instead finds Tyler Joseph and Josh Dun playing two pool cleaners who encounter a furry alien creature named Ned during their rounds.
Speaking to the Russian social media service VK, Tyler Joseph explained that Ned is "a very important person" to the duo, and in the video they're introducing him to rest of the world.
"Ned really does kind of represent a lot of things but specifically, I guess you would say it really represents this idea of creativity and trying to take care of it and trying to please it, or appease it," Joseph added. "It's kinda that thing in you that tells you whether or not something is good. And when you get to the stage that we're at, you realize that listening to that becomes more and more important because a lot of people start talking and trying to influence you and the decisions you can make creatively.
Yeah, Ned saved us," he concluded. "We made the record we made because of Ned."