Both Clarisse McClellan and Mildred Montag can be perceived as victims of their environment and the technology of their society. Both women die prematurely in completely needless, senseless fashions: Clarisse is killed by a speeding car, and Mildred dies when her city is fire-bombed.
Bradbury makes Clarisse's death purposefully empty and tragic to contrast her vitality and love of life. She is truly a victim of the fast-paced lifestyle embraced by the futuristic citizens. At the same time, Mildred's death reinforces the vapid, shallow lifestyle of her society. The reader does not actually see Mildred's death, except through Guy Montag's imagined account as he hopes that she realizes how brainwashed and robotic her beloved television and society has made her.
Bradbury uses both women's deaths as a warning about the dangerous acceptance of fast-paced living, mass media, and technology.
Clarisse is a "lover of life" and her death underscores the dehumanizing of society.
Mildred - she emphasizes shallowness. Her death shows how her acceptance into the military lifestyle is her downfall. She is clearly shallow, surrounds herself with shallow friends and even selects a presidential candidate based on looks alone.