It looks like someone is regretting lost opportunities from the past. Of course, the key in these situation is not to look backwards, but on the possibilities to come. Pun very definitely intended.
The style is clearly of a Japanese Manga, but I’m afraid I don’t know the artist. I think it’s from a series called Prison School. I found it via the Lunar Black tumblr.
Check out Prison School on Hulu,, Intense.