How does Perseus save from the sea monster?

Perseus saves Andromeda from the sea monster Cetus by using the reflective shield given to him by Athena. When he encounters the monster, he holds up the shield to avoid its gaze and then uses his sWord to attack. With a swift and decisive blow, he kills Cetus, freeing Andromeda and ensuring her safety. This heroic act not only saves her life but also leads to their eventual marriage.