In principle, I approve of this show. The idea's interesting. The characters are likeable. Miko can see terrifying ghosts, which she copes with by pretending that she can't. Something made of skulls, misshapen body parts and black smoke will quite often stick its grotesque face in hers and say "CAN YOU SEE ME?" to which Miko's reply will be nothing at all. She'll be looking at her phone, trying to look through the horror at something on the other side of the street and/or have a conversation with her busty and oblivious best friend, Hana.
Unfortunately, I think I'm missing some cultural background.
You see, in Japan, it's far more baked-in that ghosts are lethal. I'd love to meet a ghost. Tomoko absolutely wouldn't, under any circumstances. The desired audience reaction to this series is clearly "scary spectres, yikes, empathy with Miko". It's certainly true that they couldn't look more nightmarish, while the show has some outstanding horror set-pieces (that it's playing for semi-comedy). I liked Miko unwittingly standing in a ghost queue, for instance. You'll completely understand her reactions.
However, no ghost ever hurts a human. Some seem nastier than others, admittedly, and it's implied that a handful would have done something bad to Miko if they hadn't been stopped. Occasionally, big ghosts will eat smaller ones. It's also not unknown for this show's ghosts to react aggressively or even violently if they think Miko really can see them. Nonetheless, the show's based on a premise that it never substantiates. They could easily have done so. Just one victim would have been enough. Just one. Anywhere, even long in the past. A newspaper clipping, perhaps, or a flashback with that psychic granny. They only needed to demonstrate once that ghosts are dangerous and I'd have been completely okay with the show, but no.
As far as I was concerned, Miko was a girl who kept ignoring people who were trying to talk to her. Some of them seem sad. It's rude! There are cute ones, e.g. the tiny naked old men that run around at ankle height. Sometimes I felt sorry for them. Ghosts talk to her less in the show's second half, though.
Also, in ep.11, Miko suggests that Zen-sensei adopt a cat, even though he's haunted by a black cloud of ghosts, including one of the biggest, scariest in the show. If these things are supposed to be dangerous, isn't Miko worried about the cat?
Miko herself is nice, though. Understandably terrified, but she means well and she'll try to help people. Hana is lots of bubbly fun. I got irritated by Yulia's persistent misunderstandings over Miko's power levels, but she's otherwise likeable. (Hana can't see ghosts and is scared of ordinary things like cockroaches, bugs, the dark, etc. Yulia can see spirits, but there are things she can't see that Miko can, and vice-versa.)
There's a bit of fanservice, mostly in the early episodes.
It's an ingenious show. I like horror and I enjoy the ideas and presentation. It can be extremely sinister (e.g. the spectral axeman in ep.8, or the giant handprints slamming against the window in ep.9). On the other hand, though, the show doesn't really have a plot until the last few episodes with Zen-sensei, to some extent. (He had a ghastly mother. Good grief.) It's more of a "day in the (un)life" show. Sometimes I even disliked the lack of communication even just between the humans, let alone with the ghosts. There's quite a lot to like in this show, but also a fair amount that I, personally, disliked. Or at least I'm not in a hurry to rewatch.