Greek and British Unite

-- Takes place a year after the war with Gaea and 7th year for the trio (they came to Hogwarts)--
A year after the war with Gaea Hecate feels something stirring at her British school, Hogwarts. A group of ancient Greek monsters following a wizard who goes by Voldemort was planning to attack Hogwarts, but wands couldn't do much against these beasts. A quest for demigods to quietly aid in the efforts of the Wizards was needed and she knew just who to send.
-Hazel Levesque, as a controller of the mist, she would be able to get them out of tight spots
-Nico Di Angelo, being able to summon a whole army of undead warriors would likely come in handy.
- Annabeth Chase, A daughter of Athena, she had proven herself countless times aboard the Argo II and the group needed her intelligence.
-(Percy and Will also come as Percy couldn't leave Annabeth's. Even though they aren't together [yet] Will's very protective of Nico and didn't want him summoning the dead without a healer around. Frank wanted to come but he's a praetor and couldn't leave Reyna alone again.)
--Others might come later, haven't decided. Frank will probably visit cause he's a fluff ball.
-- I know in the seventh book Hogwarts is in kinda a bad place. In this McGonagall was able to keep death eaters out. Mad eye moody (the real one) will be DADA instructor, but death eaters will still pose a threat outside of Hogwarts.
---------------------------------------------------------------------------------------------------------------------------------------
As far as ships go, this will stay pretty close to the story, especially for the demigods, but if there's a Harry Potter ship I just need to see and others want it too might stray a bit from the story.
Obviously I don't own any characters, other than a character I just throw in for a filler that probably won't say more than one word. Any author notes will be bolded.