black sack
dark park
A shadowy gap.
Yes, a hink pink for "dark crevice" could be "gloomy groove." Both phrases feature a dark or shadowy description followed by a similar sounding word with a different meaning.
tan man, Dark Mark
night sight
gray day, bleak weekgray day, bleak week
Hink-Pink is a game in which player guess a pair of rhythmic words. e.g Ocean-Lotion, Funny-Money
Thin inn is the hink pink for skinny hotel.
The hink pink for "boy's test" is "lad's quiz."
A crevice is smaller than a cave. I would go with "black crack."
"Man pan" is a hink pink for male pot or masculine skillet.