an "air barnacle"; a human crustacean with a low social awareness, which attaches itself permanently to a single acquaintance in public settings. Arnacles feed by nursing a sole beverage and discussing old or irrelevant topics with their host; synonym of leech.

A phrase to describe someone who is cognitively degenerating. Synonym of "going off the deep end". Can have varying degrees of severity.

Reference to the song "Hey You" by Pink Floyd. The line "and the worms ate into his brain" makes no sense in an otherwise linear and literal narration throughout the lyrics.