So now I go into critique mode. XD
I really love how this turned out. IT's a really simple yet effective composition, and the body language reads really well. SUch a great expression of apathy best enhanced by the half droopy eyes, and the crease at the corner of the mouth. He's got that dazed look, staring off at nothing in particular while his tail lazily curls around the bar stool, though his ears still alert and perked as if in a manner of curiosity. Really great lackadaisical gesture of the hands, his one arm perched on the counter, though I wonder if his other arm holding the cup could further enhance the body language by drooping more, as if too lazy to hold up his own shoulders to even hold a cup.

As far as the colored image goes, the colors are really harmonious, at least on the character. He has warm greys, as it's somewhat of a purple tint to his fur and jacket, as well as a redviolet to all the reds in the composition. Even the jeans are a warmer form of blue, leaning more on the purple end rather than a blue grean tint, which is all great. Then you have this blue green background, (and when I say blue green, I mean in the subtle tense; if you were to look at it on the scale it is leaning more towards blue green rather than yellow green). It adds a striking amount of contrast as all your foreground elements are warm then you have this more vibrant, opposite on the color spectrum green. This bright popping contrast takes over the mood of the piece, and makes it so lively and jumping, opposite of what I imagine was your intent with apathy. Contrast ads motion to a piece, a sense of liveliness and action so to tone it down, I'd say knock back the contrast of the background, and turn it more of a warmer tinted green if a green at all since red is the prevalent hue in the foreground elements. While yes, the warm tints will help to advance on a receeding blue color scheme, a more monotonous color choice would help to, again, enhance the mood. I would even suggest a whole blue palette, as there is a psychology to color, and warm suggests a homey, and inviting atmosphere, which may be desireable in this case, since he's not necessarily depressed, but rather, comfortably contemplating life. XD

NOW when it comes to the black and white piece, I like that one better. It helps to knock back the distracting colors, and harmonize the whole image, and of course lack of color best fits the mood of apathy. It has a good balance of contrast within the tones; there's some nice dark darks, some great medium greys, and light greys, and the amount of contrast shifts between ALL these tones in the face, really helps draw our attention where it needs to be regardless of the blinding white of the counter side.

When it comes to shading, you have a good sense of mark-making when it comes to the shapes of the shadows; they have a certain animated style about them however, a solid light source would help. His jacket seems to be self-illuminated, because the highlights are all centralized,a nd the darks just outline the figure. This flattens out the volume of a character, however you're more on the right track with the jeans, where the shadows only follow along the bottom left of his leg, suggesting the light source is from thje top right. Consider studying up on light sources and shadow shapes to get the most volume out of a two dimensional piece.

Other than that, I super love this piece, and thanks for sharing!