what is sibilance?
definition
Sibilance is a particular type of alliteration using the letter "S" at the start of several words.
explanation
The repeated sound is fun to say and hear and it brings the reader's attention to certain words, giving them more emphasis. With the "s" sound it can create either a soothing effect as it makes a calming shush sound or it can be considered sinister as in "the snake slithered slowly". You would have to make a judgement based on the combined content of words and sound before explaining it further.