Amend her programing slightly

Frustrated you shake your head and put your cock back into your trousers. You know that Cassie wants you, but the stigma of you being your brother is stopping her.

You decide that to consult the 'trouble shooting' section of the manual that came through the post prior to Cassie's arrival. Flipping through the section you find the relavent question.

"How can I modify my shemale's behaviour". The book gives a key phrase that you should say and then you can alter your shemale's memory or general behaviour.

You knock on Cassie's door and enter. Cassie is lying on the bed crying.

"Cassie. Cereberal ammendment" you say.

Cassie stops crying and doesn't move, her eyes glaze over.

"Cassie, we aren't actually brother and sister we are step-brother and step-sister. Confirm"

Cassie's eyes twitch slightly as the new programing is assimilated "Confirmed" she says flatly.

"End cereberal ammendment" you say and leave her room.