Hey there, you have done a good job with the shading!
I really love those Eyes (yeah i have an eye fetish... judge me XD) and i really appreciate that you have drawn different shapes for them. Iam really curious about the Backstory =)
only one thing is kind of bothering me though... iam not sure why but the hard Shadow under both chins are making the Faces appear to be flat, but there is nothing wrong with the faces themselves though. That would be the only thing for me i had to critique.
Keep up the good Work and have fun drawing!! =)