Pretty sure that’s a rhyme
If a story has an unreliable narrator, you should still trust what they say, although you must take it with a grain of salt. The narrator could still be telling the truth, although if they are insane they may describe seeing a ghost when there wasn't really a ghost. An unreliable narrator does not create a fake story, only an unreliable story, where there may be holes or lies weaved into truth.
“because the train will arrive any minute”
adverb clauses usually start with because, after, if, although
A Simile. This is because it is comparing the muck to a leech using the words "as if".
