I like the layout, I thought the joke was funny, but I will say that you need 2 things;
1) Photoshop.
2) Graphics Tablet.
You've got a pseudo-pixel-art sort of thing happening there, and I'm not sure if that's intentional or a product of the program you're using.
However you seem to have an adequate grasp of proportion, and posing, so if you're thinking of getting serious with this, you need to invest some time and money.
A bottom-of-the-line graphics tablet can be purchased for around $100.00 at most any computer store. They work great! You will, however, have to re-wire your brain when using it... because you'll be drawing on a surface, but watching your drawing appear on a screen, a foot or two away. It takes a lot of time to get used-to.
I just cannot stress this enough; if you want to start a webcomic, or if you plan on doing a lot of digital drawing, you NEED Photoshop/Corel Photopaint & a graphics tablet.