sneakingly (adverb)

1. During World War II, spies were sneakingly collecting valuable information from enemy countries.

2. The protagonist could feel someone sneakingly watching them from the darkness, sending shivers down their spine.

3. The devil sneakingly whispered tempting thoughts in the hermit's ear, trying to corrupt his devotion to God.

4. The supervillain sneakingly stole the diamond from the museum, leaving behind only a smoke screen and a puzzled security guard.