#40 in 1980.
One that isn’t so weird until you think about the implications:
“Heaven’s just a sin away” that is basically about two people about to gasp fornicate.
Except that the recording that went to #1 was done by a father/daughter duet. That’s even creepier than the Donny/Marie love song duets where they look lovingly into each other’s eyes while singin.
The stuff from Reunion AKA Joey Levine that was played on the radio in the mid-70’s was always pretty weird to me. And they played both those songs to death around here.
Man, this thread has some good music. 
No-one mentions Shoes by Reparata? I loved that song when I was a kid, and remembered it, and finally found out what it was in 2010. According to Wikipedia, it only hit #48 in the UK, but it was #6 in South Africa.
That is so bizarre… I think I like it.
Actually, some of the lyrics are in French. 