Read them, but still there stays the feeling that something is missing and more important there is something that is to much. For me it feels like a new story and a new MC. The old MC wasn't a trans. (yes trans, not futa. Futa have both gender genitals at the same time) The only thing both stories have is the general look of the MC and that he meets the same persons. Another thing is the changing of the contract. As far as lore about demons like succubus goes they can't change a running contract or they in breach of contract and their victim is free.
It's nice to get a little quote from demonology. In fact, Avi has not changed her contract. MC is still a girl, but she also has the bonus of a penis that she may not even use. Avi has made it clear that she won't let MC go for nothing. She, like any succubus, needs to corrupt the MC as much as possible by any means necessary.
That's why she did a little "witchcraft" on the MC's body, and improved it, nothing more.
In any case, things will be plot driven further down the line as you go along. I like a little understatement when writing a story, it adds to the intrigue.
But unfortunately, my innuendos are often met with hostility and only see what's on the surface. Not one step to the right, not one step to the left.