Here’s mine, this made me lose my shit
rule34.xxx/index.php?page=post&s=view&id=5395800

rule34.xxx/index.php?page=post&s=view&id=8243806 Dunno if this counts, but I found it funny.

Does it need to be hentai specifically? I have a habit of mixing porn "shitposts" into my favorites because laughter is just as important as horny to me.

My contribution for now. More to come later as I re-find them.
rule34.xxx/index.php?page=post&s=view&id=4194292