Use it as the first accent in a reveal sequence, then follow with Enemy Spotted when the hidden character is noticed, and add a Pop Sound Effect as the visual fully lands to close the gag.
关于此声音
This is a very brief, high-pitched whistle lasting around a second, sharp and clean enough to read instantly as a tiny accent. It feels playful and mischievous, adding a light jolt of surprise without turning harsh or dramatic. That quick, cheeky character makes it work as a cue that something odd or sneaky has just appeared.