I'm gonna give age ratings for all of these so yall don't get traumatized by tpn or demon slayer and it'll be my fault. TPN (The Promised Neverland): Meh, pretty violent after the first few episodes/books. Age rating is TV-14 but im eleven years old, so... i also watch demon slayer and wednesday so ig im just special UwU Demon Slayer: more violent than tpn ig thats why its rated ma. yep ya might wanna hang tight for this one SI-VIS: Now, this one, this one you could probably watch (talking to anime noobs) mild violence, basically a more serious version of k-pop demon hunters (I WAS A GHOST I WAS ALONE HAAAA) but ALL the songs are fire, not yet rated since its so new there's only like 5 episodes as of writing this. Twisted Wonderland: its a disney anime i guarantee you could watch this and not end up in therapy for the rest of your life. its basically alice in wonderland but with a magic school and alice is a grown man- MHA: YAASSS my favorite rated tv-14 cuz its like violent or smth (aint that always the reason though) Seraph of the End: tv-14 as well, this one's like super old (2012, guys) but has a great plotline and i 100% recommend it! Bad news is only the manga is available cuz they took down the show :((((( Blue Exorcist: also tv-14 idk for some reason i dont have much to say about it. good tho Fire Force: tv-14 and for a good reason (like always) Overall, si-vis and twisted wonderland are like the "safest" ones to watch if you're just trying out anime and haven't watched, like, the marvel movies or wednesday. yep thats about it.
DISCLAIMER: this is all my opinion except for the age ratings don't come at me after watching tpn and being like "WAHHHHHH IM SCARRED FOR LIFE CUZ EMMA ▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇" eep no spoilers teehee