I hope I can offer some help, as sequential arts is my major at SCAD D8 I hope I do it justice. I'd LOVE to help you more when you get to the panels and pages, but I can offer some advice in advanced. ((mentioned after the critique))

It is a classic composition, and the juxtoposition of the older Kaibutsu vs the pup version in the foreground gives a clear telling of what the manga is going to be about. Before reading your description, I could easily make the connection that the two pictured on the cover was the same character at different stages in life, due to the continuity in the patterning (great job on the subtle pattern around his eyes starting to form in the lighter color). I love that you chose a higher saturation for the pup version in the foreground. It helps to advance him in the picture plane and really tell the viewer what the focus of the story is about.

Also good job at overlapping. It is difficult with this simple composition to have the two figures readable. The silhouette may create an awkwardness as the pup seems to follow the form of the older's snout. However, this is nicely dealt with how you have the paws jutting forth into space, creating a nice balance of negative space. If you wanted to improve this silhouette, I recommend opening up the space between the pup's two front legs, and giving us some negative space there.

As far as cover design goes, however, the text could use some work on the placement. The title is a good size and commands the attention due to placement and size, however you have this great big open negative space in the bottom right corner, and being in white, creates a void for the viewer's eye to get stuck in. I find myself staring into that emptiness only to later notice the tiny words "the untold beginning." This is more like a title card than a book cover. However, the open space is a nice breather from all the contrast in contour lines, but I highly suggest filling the white with a nice subtle background; a feild or the laboratory, or something that isn't highly rendered or detailed so as not to take away from the foreground elements or distract from the lettering. You can do this part in tone.

As far as suggestions on tones, generally speaking most covers are done without tone, when done in color. I'm not really a fan of digital coloring mixed with tones unless it's a limited palette of flats. However, that's up to you. If you're interested, I highly recommend the How To Draw Manga series on toning, or get Computones or a digital toning program. Digital toning will be FAR more cost efficient to you than the actual thing. Having worked in both, I can tell you that traditional toning, while cool and fun for a little while, just isn't practical. When working in tone, think of the tone shadows as cel shading, just in halftone pattern. You can see my tutorials on cel shading and I can recomend a toning process if you are interested.

But on the whole this is a great start. It just looks incomplete without a background. I highly look forward to seeing the actual pages and to see how the story progresses.

Some general tips on sequential arts; Consider these important elements before just throwing images in panels.

Pacing: Panel proximity has a lot to do with how fast a page is read. Consider the size, shape, and proximity of panels and use them to best guide the reader through the page at a pace befitting of the story. For instance if you have a slow scene, use fewer panels to the page, larger panels, and wider panels. If you want a fast action scene, consider tall skinny panels, close together panels, less dialogue on the page. If you want a nervous, tense, action-building-up scene, consider creating awkwardness and uncomfortableness in panel layout as in; small-big-small-big ratio of size, really cramped, lots of panels, close together. Don't use slanted, diagonal, shaped panels unless absolutely necessary. I find too many artists trying to do these crazy shapes for panels but they do NOTHING for story.

For more information on the subtleties of storytelling through comics check out ANY of the books by Scott McCloud. I highly recommend Making Comics by Scott McCloud. There's like. a whole other world of comic making that I never used to know about till I studied it in college.

I hope this has helped! I truly am excited to see what comes of this n.n