I can't be arsed to transcribe the actual title, going with the store label.
https://sasizume.booth.pm/items/574966

That looks like it hurts as hell...

Base +6, lokofunk +6, Naru42 +6, xyzdragon +8, Xymena +6, George642 +9, Alokrhea1 +6, Ictiosis +4, Extiandr +13, ShowMehYaMoves +6, Papilioeal +12, sifangbazhu +5

I didn't ask for nightmare fuel when I saw those tags. Those tags normally mean something else, anything but this.

Base +7, lokofunk +6, primeemu16 +7, Naru42 +6, George642 +9, Alokrhea1 +6, akoldon +5, ninjaboy196 +7, Extiandr +13, PC-Reviver +11, Phears +4, Enki17 +10, Papilioeal +12, and 1 more...

Hmm, that is one way on how not to enlarge your penis..... Or is it one way on how not to enlarge your breast???

Thanks @Maximum_Joe

Base +6, Papilioeal +12

the worms are making holes in his balls

you really shouldn't put your dick in everything that looks like a vagina, especially if it's alive

Base +12, Xymena -6, George642 +9, sword122 -6, Ictiosis +4, ninjaboy196 +7, Temperature Critical +26, Bonbon88 +6

Wear a condom kids, even if you're fucking a fish

Base +6, akoldon +5, Ictiosis +4, ninjaboy196 +7, UnGtx -11, Temperature Critical +26, Bonbon88 +6, Papilioeal +12

The basic plot of this is that the main character is a transwoman who doesn't want her testicles anymore (it's common in Japan for transwomen to get castrated to reduce testosterone), but "surgery is expensive" so she goes to the "Anazon" river to deliberately get this horrifying parasite to destroy her balls. This is why she has breasts in the second page after being pretty flat in the first one. The parasites growing in her testicles are releasing some kind of anesthetic that keeps it from being painful, which wears off after they all come out (hence the last panels of the final page).

Base +7, Blind Wolf -6, WiND221 +6, ninjaboy196 +7, twilight0617 +9, Phears +4, Circumstances +11, Maximum_Joe +64, Enki17 +10, Uwulol +5, saga +9, gaging0 +9, starburst98 +6, and 13 more...

Page 3: Parasite says "Hi <3"

Base +8, Bonbon88 +6, Papilioeal +12

The parasite is so cute <3

Base +9, Papilioeal +12, unbalancezone +2

Cute dickgirl

Base +3, frontalline +3, livingprivacy +3, imhavingfun +3, wsimple +3, memoryofpast +3, quietlynights +3, airyways +3, unknownvisitor +3, weirdmatters +3, somethingmystery +3, passthrought +2, Curiousledge +2, and 7 more...

草草草草草

Base +5