Finished 密告はうたう!
Ahh so good! A cop has to investigate his colleagues on suspicion of being a mole and he struggles with doubting his fellow officers while simultaneously being ostracized by his org due to an incident where his partner was murdered…which likely is tied to the mole. Oh, and no one likes the police officers who investigate other officers.

I love this kind of intrigue. It has the perfect pacing to make it very bingeable. The only thing stopping me from finishing it sooner was the number of hours in my day after other obligations.
For people who don’t like violence this is mildly violent. There is on screen blood, but they go out of their way to edit so that you don’t see much for graphic injuries and such.
I’d put this at slightly below the difficulty of 桜の塔 for me. There aren’t as many new words, but the longer conversations sometimes were rough. I suspect this is the type of show where whenever I rewatch it I’ll wonder why I struggled at all; it’s right on that cusp. If I’m not simultaneously watching body language, trying to analyze the most recent developments in the story, AND parse Japanese it’ll surely be easier. 
I also decided to try out some new shows today as I had a bit more time than usual. Gossip I didn’t even like enough to finish the first episode, but the first episode of3年A組 seemed super promising. It’s about a teacher who takes his classroom hostage. The only off thing about it for me is that it can’t seem to decide if it wants to be a comedy, a drama, or dark. Those all can be balanced/combined, but I don’t think it’s doing a good job of it. I still like it regardless and plan to continue watching, although I’m curious how it will progress as the hostage situation is “planned” to last 10 days, there are 10 episodes, and each day a student is killed which seems like maybe it’ll get strange after awhile? Like what is he doing with the bodies? He just dragged the first kid into a room but he blocked off the majority of the school so there’s limited space…?
You should have them watch 哀しみのベラドンナ/Belladonna of Sadness. As someone who isn’t into, I suppose you could call it “tropey anime”(?), I quite enjoyed that movie. It’s actually rentable on youtube and it’s more of a dark 70s art trip than what most people would think of when they hear anime. It is NSFW however for rape (central to the plot), copious nudity, and general violence IIRC