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.
Big Lipped Alligator Moment: Every single time where Rei's masturbating. Even more jarringly the second time, which is totally out of context and downright silly.
Demonic Spiders: Wolves as mentioned: they're very fast, offer a smaller target, can attack you quickly several times in a row if they get close enough and deals a lot of damage. Hope you got some sushi on you if you stumble into one.
Goddamned Bats: Bamboo traps. A tiny target which deals annoying damage and can't be blocked.
That One Boss: Red Fox is obscenely fast, always slashing at you with her sais when she's not casting flames at you. Furthermore she does teleport after each attack, meaning that you have a very small opening to strike at her. Last but not least, she has tons of health points.