Red Light is basically a social commentary song
The lyrics are criticizing Korean society.
f(x) members running away with Resistance look
from gas masked people in the smoke implies
their distrust and opposition to the government.
Emergency red light is the warning system.
Burning book is failure of useless safety manual books.
Odd eyed cat is abnormality and dissociation of ideal and real.
All these together reflect and criticize
the series of recent failure of Korean government safety system.
When they sang a word "sink" It immediately remind me of Sewol Ferry.
I was surprised that f(x) went this much profound.
I wrote longer and detailed version of interpretation in Korean
and working on translating to English.