concealed
all fours
back-door
backstairs
clandestine
covert
cowering
crawl
crawling
creep
creeping
cringing
crouching
deep-rooted
deep-seated
devious
doggo
duplicitous
feline
furtive
guileful
gumshoeing
gut
hidden
hidden out
hidlings
hole-and-corner
hugger-mugger
in ambush
in hiding
in the wings
indirect
inherent
innate
intuitive
lingering
lurking
mean
nagging
niggling
nightwalking
on tiptoe
padding
persistent
private
privy
prowling
pussyfoot
pussyfooted
pussyfooting
quailing
creaking
critiquing
eking
freaking
leaking
peaking
peeking
reeking
seeking
shrieking
speaking
squeaking
streaking
tweaking
wreaking