These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Ushio and Tora
Complete Monster - Hakumen no Mono qualifies (apart from being, well, a monster). Personally and through its various spawn and underlings, its hobbies include bringing down countries from within, stealing a newborn baby for dastardly experiments, and just plain killing stuff.
See here for a fan-spliced example with Kirio's 'mother'. The fiend! Which deserves more explanation. She tricks and lies to Kirio all his life to manipulate him to destroy the Beast Spear. She even killed his 'father' and began manipulating the Sect to join Kirio after Ushio had failed to stop Hakumen's Bushin before. When she dies, she says everything she told Kirio is a lie and she lied to him AGAIN when he asked if she really loved him.
The Kamatachi duo's Evil Counterparts from the West. These psycho siblings relish in death of anyone and they use their cutting powers to inflict as much pain as possible. While Raishin and Kagari love each other, even respecting their brother's legacy and defend it, these three don't care two shits about what happens to each other. Its satisfying when Tora, Raishin, and Kagari manage to defeat them.
Crowning Moment Of Awesome: So very many, but I think the weak Izuna, when told things would be decided in a battle, and he was the only one not locked up, all but immediately said, "Okay, where's my opponent?!".
Crowning Moment of Funny - The very first episode, when the then-unnamed Tora asks Ushio to free him from the spear. Ushio asks what Tora intends to do, and Tora replies that he'll eat him first and spread terror among humanity, heheheheHAHAHAHA~ooooooooowwwwwwww!!!! as Ushio starts stomping the spear deeper. And then he slips up and repeats the SAME THING when Ushio gives him a second hearing! Youtube here. Tora really can be a moron at times...
Ushio and Tora also qualify! When the bakemon Kuin mocks Ushio's weakness, stupidity and lack of training compared to its master Kirio, Tora beats the crap out of it, then says to Ushio: "I don't know why I got really p*ssed off when he was saying that crap about you... BUT I still hate your guts!"
Tear Jerker - Lots, see Complete Monster entry for just one example. A good deal of the Bakemono in the story are given quite sad backstories.
One in particular is the death of Hizaki Mikado.
The part where either Asako or Mayuko must sacrifice herself to make a new Beast Spear that has everyone crying, even the bakemono who don't really want to do it either but have no other recourse. The whole arc becomes one long tearfest as important characters one by one vaguely recall someone who touched them Ushio and Tora but because of an enemy's attack, can't remember exactly who and why.
Nagare's backstory and reason for his Face-Heel Turn, as well as how they are revealed. The Hakumen no Mono enjoys causing this sort of thing.
The Woobie - You will want to give Tora AKA Shagakusha a hug once you learn his backstory. Same goes for Hyou.
So, SO many characters.
Some of the bakemono enemies even, though it doesn't excuse their reaction of massacring all humans they meet.
Uncanny Valley - So, Our Monsters Are Weird yes... Now add assorted limbs, faces and naughty bits that look COMPLETELY like an ordinary human's on almost random places on the bakemono's body, and it gets even freakier. Examples: A perfectly bad-ass looking crab bakemono which is then revealed to have HUMAN FACES on the inside of its claws; numerous lesser bakemono with mutiple HUMAN ARMS AND LEGS instead of more practical for fighting claws.