eerie, frightening, morbid, hair-raising
scary
Frightening
Frighten
eerie
scary or eerie
The void was very dark and scary.
Horrendous Love?
One close rhyme is the word "merry" (fun). Another possibility is the word "airy" (light, pleasant).
Horrible, scary, disgusting,ugly..
Creepy, scary, unnerving, spooky.
scary, horrifying and/or frightening
the kids entered the dingy, dark, and scary chamber