She resists the effects of the compulsion

Bulbous and veiny with curly hair matted to both the shaft and the wrinkled sack below by a mixture of glistening white semen and Harry's own secretions. Considering it was attached to the ugly fat arse that was her uncle, the cock should not have been nearly as enticing as it was.

'And yet...!'

Harry's eyes were locked onto the organ that had defiled her - that her uncle had **** her with.

[Submit.]

[Clean him off.]

[Obey men.]

Harry's magical compulsion rang in her mind and gently urged Harry to give in to her uncle's whims and follow his last order.

"...No..." muttered Harry.

[Submit!]

[Obey men!]

[Submit!]

Harry gritted her teeth as the magic of the Oath started to squeeze her chest, making it difficult to breathe.

"No...!"

[SUBMIT!]

"I WON'T!" shrieked Harry and her magic flared against the Oath that constricted her body, snapping the ephemeral chains and causing the windows to rattle in their frames and the room to shake before settling down.

"Snrk...Blasted...freaks..." Her uncle wasn't roused from his slumber, though his mumbles drew Harry's attention as she regained her breath from fighting off the Oath.

Anger rose up within Harry of what he had done to her - of what she had let him do to her. Harry was only here in the first place to help the Dursleys move back into their old home to repay them for being driven out of it when Voldemort was still around. Granted, Uncle Vernon clearly didn't know she was actually his nephew, but the memory of what had happened, of what she had gone through growing up with the Dursleys stoked the flames of anger in Harry's heart.

Tssst... Crack! Crack!

Harry's wand was in her hand, the point of which was trembling as her roiling emotions translated to numerous sparks and flashes of light to be intermittently released from the tip. While her arm shook, Harry nonetheless raised her hand up until her wand was pointing directly at her sleeping uncle. She was eighteen now and thus there was no longer any Underage Magic law protecting her uncle from his rightful comeuppance. There was no one in the house at the moment besides the two of them and she wasn't in front of a window either.

No witnesses.

No Ministry interference.

No one to stop Harry from doing what she wanted.