Place it at the reveal point in your edit, just as the figure becomes recognisable, then follow it with a sudden scream or a dramatic sting to sell the scare. For a funnier cut, answer it with a denial sound right after.
Over dit geluid
A voice asks 'Is that Freddy Fazbear?' in disbelief over about eleven seconds, stretching the question out for comic effect. It feels startled and funny at once, like spotting something you really hoped was not there. The line references Freddy, the animatronic bear from Five Nights at Freddy's.