I found this on YouTube. It's not really a parody, it's more like if the theme from Stranger Things had lyrics.
It's amazing and I love it. It's by The Warp Zone.
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Lyrics:

Hello there I'm gonna sing
A ditty about Stranger Things

I hope you are all listening
or you won't know what's happening

A boy's abducted in the forest
By a scary Demogorgon
Friends go out there looking for him
Find a girl who's kinda foreign

While the kids are bold and brave
The grownups are not well behaved
Their judgement comes and goes in waves
They smoke and drink in sad man caves

And pop prescription pills while working
Hit on women while they're working
Drink at bars instead of working
Beat up folks and call it 'working'

And the parents? Where to start?
Their negligence is off the charts
Parenting is not that hard
If you know where your children are

Also what about poor Lucius?
We don't see his parents once
I'm sure that they're concerned about him
Is his dad that other cop
Cuz he's the only other black guy
But I don't mean to assume
I hope this isn't sounding racist

How 'bout Barb?

Everyone forgot about her
Nice detective work there Hopper
But let's pin the blame on Nancy
Couldn't keep it in her panties

If the parents paid attention
Maybe Barb would not be dead

But I guess the scientists
Who run illegal tests on children
Probably are the worst adults
As far as bad behaviour goes
Forcing El to use her powers
To confront a scary monster
That is straight up child abuse
So I'll let Hopper off the hook

So to sum up Stranger Things
The kids are cool, the adults suck
I guess I coulda said that at the top