Were they shagging each other while Moses was away??
It appears obvious when Moses returns; the way Jill looks at Shades gives the impression that something went on between them. She blanks Moses and talks directly to Shades most of the time, maybe because she was pissed off that Moses left her...
Shades appears to be very jealous and uncomfortable when Jill hugs Moses before the shower sex scene and decideds to leave...
I always felt she was uncomfortable around him. She seemed to be creeped out. He was a bit too eager to help. The "I wish that I had Jesse's girl" syndrome, when you like a friends girlfriend.
I suppose you could see it that way considering Shades says to Moses that he had been "keeping an eye on her".... but I reckon there was something more ;)
I don't think they were, but Shades wanted to. The whole "keeping an eye on her" comment seems like more of a stalker than a lover trying to keep a secret. Also, I rather get the impression that Jill considers Shades to be Moses' friend and not hers at all, just some weird little guy she puts up with because he's Moses' best friend. Then again, maybe Shades is just really lonely. And hey, who doesn't get uncomfortable when your best friend, back from space, totally ignores you to make out and have sex with his girlfriend, practically before you leave the room? :)
Of course they are. Shades knows that he will always play second fiddle to Mo when he returns. Hence his sad look when he leaves the apartment and his getting mashed on his drugs later on to try to get over it.
I got the idea that maybe something had happened between them, but it wasn't going to go anywhere because he was never going to be more than a stand-in for Moses.