This show is jam packed with little details like this. Like the final episode, titled Felina. Break it up into Fe, Li, Na. Fe, or iron, is found in blood. Li, or lithium, is an ingredient in meth production. Na, or sodium, makes up a large portion of tears. Therefore, Felina can translate to Blood, Meth and Tears.
Apparently the lithium part was fake, someone thought it meant that but Lithium isn't actually used in meth. On the other hand lithium is used to cure bipolar so maybe it something got the do with mental illness.
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