How does irony appear within the poem entitled “candy-striped” (81)?

When Anderson’s candy-striper job requires that she take some files to the morgue one day, a young man asks her for her phone number. Rattled by seeing a dead man’s hand sticking out from beneath a sheet, Anderson gives the young man her number. At first, the young man goes slowly with Anderson, causing her to feel relief. She says that on their first date, they saw a movie, while on their second date, they went out for pizza. Pleased with how his pace is matching hers, she is shocked when in the front seat of his car, he tries to force her head down to his crotch.