Is there a way to keep the male origin?
If you mean the MCs old body by male origin ... nope ... that´s gone for sure ...
If you mean the MCs old mindset by male origin ... I can´t tell for sure ... but being (trapped) in a female body will corrode his origin over time ... until it completely fades away ...
I don´t think your MC can keep his male origin forever ...
When you chose a perk (mid game) or gain a perk (exhibitionist, second day at the beach), the MCs will act as if he was always a female
Althrough, It's not that big of a deal since I've only noticed it when the MCs do a sexual act for the first time, it still feel wierd.
The story still recognize your male origin though.