When Sunset realises that none of her human friends ever really apologised to her after the Anon-A-Miss incident, she leaves CHS to find better friends who wouldn't leave her at the drop of a hat. She eventually decides to go back to school, but is tripped on her way in and sent flying through the portal.

Instead of going to Equestria, however, it transports her to just outside of Camp Half-Blood.

Adventure and shenanigans ensue, as Sunset finds new friends and family at Camp.

Based off Percy Jackson, as well as all interrelated series, (Heroes of Olympus, Magnus Chase, Kane Chronicles etc.)

Set just after The Last Olympian.

I highly recommend you read the Percy Jackson books first so you know what you are getting into.