What is the primary goal of Keima Katsuragi in The World God Only Knows?

Keima is forced to help a demon named Elsie capture runaway evil spirits hiding in girls' hearts by making the girls fall in love with him, later expanding to awakening hidden goddesses.

Why does Keima have to help Elsie capture the spirits?

He accidentally signs a demonic contract via email, resulting in an invisible collar placed around his neck that will decapitate him if he fails his conquest missions.

What happens during the time travel arc at the end?

Keima is sent into the past by the goddesses to fix altered historical events, team up with a mysterious girl, and stop giant humanoid monsters released by a rival demon faction.

Does Keima get rid of the deadly collar by the end?

Yes, after completing his final mission in the past, reconciling with a giant monster, and averting disaster, Keima is finally relieved from the collar and returns to his normal life.

What are the Jupiter Sisters in the story?

The Jupiter Sisters are six powerful goddesses who lie dormant inside the hearts of specific girls whom Keima and Elsie previously helped conquer and clear of loose spirits.