Okay now you have the complete opposite of the length issue 
Alright alright here me out, it's better to have a shorter blurb than a longer blurb, but considering that I've been reading your comic for quite a while, I know there is really a lot more to your comic than the blurb lets on, and I think other people should know that.
The plot of your story is essentially about a rock who's "the chosen one," and while the audience (and Kimura) can clearly tell he's just a regular rock, everything still seems to work out for him, which makes it funny. You can play off that humor by saying something like:
Rocky is the hero of legend: capable of doing the impossible, not afraid of anything, faster than the human eye, and also a rock. But even with the strength of his friends pushing him, will he have what it takes to save the world?
Or well something along the lines of that. Basically, hype up Rocky a ton in that first sentence and then top it off with the fact that he's a rock. I based it on the first page of your comic, where Rocky is essentially hyped up that much and then he falls over cuz...well he's a rock lol (https://tapas.io/episode/803424)
PS: I hope you appreciate that pun I made about his friends pushing him lol. You can take it out if you want tho. I just felt like doing a silly thing there 