The Kelton Avenue Mystery Head

I was bleeding when I first saw it. Not badly. Just a skinned knee from a pratfall a few blocks back (I walked the neighborhood for exercise.)
A face peered out a window several houses ahead of me. Its plaster skin and glass eyes made me think it was a prop or an educational model. Closer inspection proved it could only be an educational model about hallucinogens.
Two heads fused at at cheek level, sharing a chin, neck and twisted mouth of clenched teeth. My depiction is stylized. The original had realistic features and was creepy. There it was, propped in the front window like a vase of silk flowers.
What is this thing? I wondered. Where did it come from? And why is it propped up in the window? Did it freak out the neighbors? The local kids? (I'd have flipped if I saw it when I was little.)
I wanted to know more. Someone had designed and built this awful/funny/fascinating thing. Someone wanted it in the front window. Why?
I considered knocking on the door and asking. What would I say? "Sorry for interrupting your dinner, but what's with that freaky thing in the window?" I never had the nerve.
Then the Mystery Head got coy. Sometimes it was there, sometimes not. I often passed the house with friends on the way to the shops and eateries on Pico Blvd. I anticipated pointing it out to them. Would they think it was as weird as I did? Would someone recognize the artist (or horror movie) behind it? Invariably, it was gone when I passed with a witness (Why? Did the homeowners bring it to the table for meals? Borrow it to freshen up the bathroom?). A few days later, I'd pass the house and there it was, staring me down with four eyes.
It's been years since I've seen it. The house was demolished and rebuilt:
I checked the windows of the new home when I passed it. No mutant heads peered back.
I still wonder about it.