Quick sketch of what Lucille and Jean-Luc look like when they're.... less than human?...

1) yes I messed up that's why part of it is folded. Shhh

2) the reason Luc usually has his wings in place of his arms is because it's easier to form them from the existing bone than it is to create them from nothing....

3) also, the reason he can do two different ways with his wings there is cause some harpies have wings on their backs while others (most) have them in place of human arms.