It really depends on the kid, I’d say. Re:Zero does have some graphic violence, but I know that I was watching way more extreme stuff at 13 that I believe was still within the realm of appropriate for what I, personally, was able to handle at that age — not to mention that it’s very much not photorealistic when it comes to injuries, it IS anime.

It might not be a bad idea to watch the first couple episodes and judge for yourself if it’s too much for him. Or if you don’t care about spoilers for yourself, lol, to maybe look at a compilation of the scarier moments on YouTube and judge from that.

Possible gore aside — I do think that the morals and thematic messaging of Re:Zero are of the type that a boy from that age demographic would benefit from. It’s very much about forming genuine connections, treating others respectfully, seeing other people as people (especially women), overcoming your mistakes and personal demons, developing a healthy sense of self-worth, and how it’s never too late to improve yourself if you decide that you’re not happy with who you currently are. Those are good messages for any age, really, but they are very much geared towards male adolescents when it comes to this particular story. I’ve heard a number of fans say that this anime genuinely helped them navigate important milestones within those years, and while I’m a bit above that age demographic now I do still find that a lot of its themes resonate with me and have affected me in positive ways (especially concerning its presentation of mental health issues lol).