Previously when I’d come across particularly clever/interesting/entertaining copy in WaniKani, I’d just sort of get a personal kick out of it myself and move on – after all, these lessons/reviews won’t complete themselves! 
But then I thought…heck, others might appreciate this stuff as well, so why not share it, and see if anyone else has some good ones I’ve missed (or forgotten: I kind of wish I’d saved some of them somewhere, as I feel like many may have gone away over time…)
For instance, this cracked me up:
いくら親しいからって、トイレに入ってきちゃダメだよ。
No matter how close you are, you shouldn’t come into the bathroom.*
I just can’t help but try to imagine the situational context here, and…as it turns out I also had multiple acquaintances try to explain the usage/nuance to me completely independently, which is also memorable.
Anyway, I’d love to hear any example sentences, etc. that y’all find to be enjoyable for one reason or another. No particular criteria, just anything that strikes you for whatever reason. 
*This is arguably not a “correct” translation, but as with so much between Japanese and English, directly translating something said/written with any flair at all just sounds ridiculous, so we just have to rise to the challenge in order to try to convey the intrinsic meaning as best we can. I guess that’s why I love it so much! 