Why did Gill leave monster high?

Gill left Monster High because his parents doesn't believe his people should be seen with Lagoona's so they sent him to boarding school but in the Fright On he came back because he loved Lagoona so much

His parents are stupit thats WHY

It was of course; because his parents could not see the love blossoming between Gil and Lagoona and never breaking the tradition of "Freshies" not being able to be seen with Gil himself and his 'racist' parents: "Salties."
This little crack in the road was nothing though, because as seen in "Fright On!" and a few webisodes after Back to Ghoul, Lagoona is reunited with her (perfect-for-her) boyfriend!
This proves that with love that is as true and pure as Lagoona and Gil's; nothing can stand in their way!❤ L❤ts ❤' L❤ve: BrrrFan

his parents did not like Lagoona so they sent him away from her

Because his parents didnt want him to date lagoona and he did so thez took him away

he moved cause his parents disagreed for him to be with lagoona so after summer break lagoona walked out of the ghouls bathroom crying then Fra n kie sorry I wrote this on my kindle Frank ie later told lagoon a that she had two boyfriends lagoon a replied that's good for you and walked away crying soon he reaturned became couple he (translation.his fresh water and she's saltwater incompetents didn't trustsalties