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: Blade of the Immortal
Complete Monster: Blade of the Immortal brings us the truly despicable Shira, who's just around the level of Yujiro Hanma in his depravity. He murders a Hooker with a Heart of Gold who was just in the business to pay for her mother's medicine, because he enjoys cutting up women and making their muscles seize up during sex. After that, he savagely, gleefully tortures an assassin with his saw-edged sword and severs the leg of the unarmed woman that led him and Rin to the trap. After losing both of his hands to Manji, Shira is saved by his employer, who asks if he's chosen a new set of hands yet; he raped a hooker (to death) and young boy (who provides his new pair of hands) all night long in his cell. Later on, he mutilates and brutally cuts a woman to pieces, gags her with her own dismembered hand, impales her through the breasts, and rapes her to death, while eating parts of her corpse. After finding Rin, he strips her of everything but an open shirt, tied huge rocks to her feet and left her tied to a dock, half submerged in water during winter. It's exceptional how well Shira can execute numerous bouts of actually appearing sincere. His heartfelt speech to Rin aims to drive in how he killed and ate her dog. Helping Renzo seek revenge is aiming to force Renzo to be a sex toy for Shira's abusive benefit. Truly emotional pleading of Renzo to call off his revenge ends with a spiteful "never listen to men like me!", which thus end up putting the latter in even worse a state than before.
Draco in Leather Pants: Anotsu Kagehisa has this in spades. There's been continuous hinting at a relationship between him and Rin.
Foe Yay: Sweet Jesus, where do we begin? With the amount of sexual tension running in between camps, it seems probable that the main cast will just engage in some giant orgy as soon as kill each other.
The Woobie: Makie, who is an unbelievably tragic figure whose life has been nothing but suffering, pain and isolation. The man she loves values her more for her skill than for her as a person, her relationship with her family was dysfunctional at best and she has no purpose in life that she can name. All she can do is resign herself to her own lonely corner of the world and life quietly, troubling and being troubled by none.