Much the same as beer goggles, though no alcohol is required; i.e the man's schlong makes a terrible, terrible decision about a girl best left alone. The brain is hardly involved, if at all.
This may occur after many months of sexual frustration, or simply if he is a slag.
verb; to schlong-goggle
"jesus tom, what were you thinking?"
"i don't know man, i definitely had my schlong-goggles on"
"however hard tom tried, he simply could not remove the schlong-goggles from his eyes"