"Bittersweet Demons" is a song by The Murlocs from their album of the same name.

 

According to the group's frontman, Ambrose Kenny-Smith, the song and album are somewhat inspired by Harry Nilsson's Pussy Cats:

 

I was really heavily into like Plastic Ono Band, and lots of Lennon stuff. And Harry Nilsson. . . I got really into that 'Pussy Cats' album that Lennon produced with Nilsson.
Those are the two main references for how I wanted it to sound, because that was what I was obsessively listening to on a daily basis. The title track, 'Bittersweet Demons', is probably a good example of that.

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