It's a Girls World

Anti decides to force Marvin the Magnificent into doing a spell on Seán, or Jacksepticeye as the world knows him. The spell swaps his gender yes, but it also rewinds him to that of a 13 year old girl. Anti panics about the age thing, just thinking the spell would change his gender to that of a her, and dumps Jack-turned-Jane at Mark Fischbach's home. At first the victim of the spell is embarrassed and moody, but Mark notices the longer the spell lasts on his friend, the more they start forgetting things and devolving into an actual teenage girl.

Will Mark be able to find Anti and get him to fix Jacksepticeye? Will Seán lose himself completely and start over as Sara McLoughlin? Will Anti take over Jack's channel?

COVER ART NOT MINE, IT IS ARACELYZUMEN FROM DIVIANTART I THINK?