[@SSGSS Senpai] I was speaking about the ally. If you're making your ally a PC... then really, do you need to have the Ally perk at all?

Twinned soul is just that, a twin. It has the exact same stats as you, but you both have -1 in all stats and the effects of Silver coins are halved on both of you, and I'm pretty sure the use of Bronze coins do not affect your twin. The only things the twin rolls for are weapon, outfit and power, which for some reason differ. Otherwise, they're an identical copy of you. Same age, body-type, specialization and same perks.

The twin CANNOT be made an additional PC, for, really, they're already part of one. The twin is the same character again. So, yeah.

Roll 9 d20ies for a regular ally. In perks, they only get 3 combat perks. You get to chose to make them a regular girl who can then spend two silvers and three bronze on their stats, or make them a monster girl with benefits and drawbacks as you pick and no coins. That's about that. They're not MEANT to be PCs. Just NPCs that hang along with the character. That's what the Ally perk is supposed to give you.

Edit: I should note that this is just how I personally have interpreted the rules. If the GM says otherwise, then otherwise goes.