"The Rape of the Lock" is a mock epic or an "heroi-comical poem" as Pope describes it in the epigraph. The poem uses the form, tone, and seriousness often reserved for genuine epics which are usually based on significant struggles such as war (The Illiad) or the battle between good and evil (Paradise Lost). A mock epic uses these tropes but the subject is not as grandiose. This is a battle/argument between men and women. The tone is high and serious, but the subject matter is trivial. 

Belinda, the main character, is invited by friends to go to Hampton Court. In Canto 2, they sail up the Thames River and during this trip, the Baron decides he wants a lock of Belinda's hair:

The adventurous Baron the bright locks admired,
He saw, he wished, and to the prize aspired. (29-30)

They arrive and eventually start playing Ombre, a card game. In keeping with a mockery of the epic form, Pope describes the card game as if it were a war or a battle between kings and queens. This is fitting, considering the use of cards representing kings and queens. Ariel, a sylph, watches over Belinda in attempts to protect her from harm. He is a spirit or her guardian angel. Still engaged in the card game, the Baron is drinking coffee and comes up with a plan to cut the lock from Belinda's hair. His cohort, Clarissa, quietly presents the Baron with scissors ("a two-edge weapon") which he will use to cut the lock. Ariel and his supporting sprites try to stop the Baron by calling Belinda's attention to what is going on, but Belinda does not respond. The Baron doesn't just try; he succeeds. The Baron cuts her hair. Ariel is cut as well but since he is a spirit, his immaterial body reforms immediately. However, the hair has been cut: 

A wretched Sylph too fondly interposed;
Fate urged the shears, and cut the Sylph in twain
(But airy substance soon unites again):
The meeting points the sacred hair dissever
From the fair head, forever and forever! (150-54) 

Belinda is horrified. Even though this is a mock epic, this act of cutting her hair is like an assault and symbolizes a loss of feminine virtue.