Look, this is Adult Swim doing what Adult Swim does—violent, stylized anime for grown-ups. The IMDB rating of 7 suggests it's competently made, and if you're into dark revenge stories with ninja-mecha action, you might enjoy it.

But let's be clear: there's zero reason for anyone under 16 to watch this, and even then, it's pretty much just violence porn wrapped in anime aesthetics. It's not enriching, it's not wholesome, and it's definitely not safe for younger viewers to accidentally stumble upon.

For parents: this isn't a "maybe when they're 13" situation. This is a "wait until they're actually 16+ and even then, ask yourself if they need more revenge-driven violence in their media diet" situation. If your older teen is really into dark anime and you're okay with graphic violence, fine—but don't expect any life lessons beyond "revenge is a thing people do in stories."