damn, a real shame honestly. i wish that stories like this would be a little more gritty and dark, especially given that it involves something as horrendously dark as child assassins. Not to mention, with that first scene of the oily fat mob boss basically fondling the male child assassin's inner thigh and the whole 'parent-child' thing, the implications about the business get even darker. Just gives it a very off-putting feeling when they try to maintain a mostly comedic tone the whole time. The action scenes are one of the only exceptions to that, though I'd be lying if I said some weren't ruined by horribly timed jokes/gags.
Basically: Keep the tone dark, stupid gags in the middle of supposedly serious moments ruin the story.
Also, it's a lot less enjoyable when no one of importance dies. I won't say more than that, spoilers and everything, but let's just say the author had the opportunity to completely change the entire tone of the story into something a little more appropriate for the plot but fumbled.