In Hesiod’s Pandora story, Epimetheus accepts Pandora despite Prometheus’s warning.
Epimetheus is Prometheus’s brother and a Titan associated with hindsight or afterthought. Hesiod presents him as the recipient of Pandora, who is sent by Zeus as part of the punishment connected with Prometheus’s actions on behalf of humanity. Prometheus advises Epimetheus not to accept gifts from Zeus, but Epimetheus does so.
Pandora’s subsequent opening of the vessel releases troubles into the human world. The episode reinforces the contrast between the brothers: Prometheus thinks ahead, while Epimetheus acts first and understands the consequences afterward. Their names are commonly explained through that contrast.
The myth does not portray Epimetheus as a heroic rescuer or as the person who steals fire. Those roles belong to Prometheus in other parts of the mythology. Epimetheus’s specific function in this episode is to accept Pandora and thereby allow Zeus’s plan to affect humanity.