Both done in ~1 1/2 hours, with Pencil & Paper.
C&C is welcome 
EDIT And yes, I know that last one is a bit disproportionate. 
They look good, except the first one needs to be shaded in that area that has nothing in it.
I like the second one better, anatomy looks good; the neck might be a bit too thick. question: are you using a scanner? if so the quality doesn’t look good.
It looks like he took a picture with a digital camera and then put the pictures on his computer.
pull them into photoshop and modify the levels (image > adjustments > levels drag the two outer sliders closer together) and contrast (image > adjustments > brightnes contrast) and optimize them a bit by saving for web.
the drawings
i like the first one alot, its like there’s a bright light shining from the top left, the second one is a little odd, i agree that the neck might be a bit too thick, and perhaps we shouldnt see a gap between her legs (you know what i mean )
Thanks for the replies! Yes, I took a picture with a digital camera, I don’t have a scanner. 
Traitor: I enhanced the contrast on both already, I’ll try that, though. 
Anyway, thanks for the comments!