The Infamous Yaoi P-List 1 (WARNING: Hardcore kink ahead!)

Desperation, omorashi- forced wetting with pants pulled down, urolagnia, voyeurism
Recommended

Yamaguchi becomes desperate to pee at a festival. Tsukki becomes aroused by watching and hearing him trying not to pee himself. He takes Yamaguchi out into the woods and presses on his bladder before ordering him to pull his pants down and pee right there. Both become aroused and have hot sex after.

★ Special thanks to TooDeepInThisShit for the recommendation

Enema, peeing during sex (seme- into uke's ass)
Shotacon, incest (brother/brother)
Hardcore and explicit (water and pee expelled from anus)
My Reading Manga website

Rentarou catches his older brother anally masturbating by giving himself an enema. He offers to do it to Rentarou, but gets overexcited by the act and ends up having sex with him. He finishes off by peeing inside his little brother.

★ Special thanks to Sayrrin for the recommendation

Desperation, omorashi- wetting underwear, urolagnia, voyeurism

On the way to the toilet, a drunk Levi ends up Eren's room. Later, he realizes he forgot to go and he tells Eren he needs to run to the toilet before he pisses himself. Eren stops him and begs to watch. Levi sits on the bed with his legs spread apart and pees in his underwear, which makes Eren horny.

★ Special thanks to TooDeepInThisShit for the recommendation

Ch. 3 - Desperation, omorashi- peeing into a tissue, pee denial, urolagnia, voyeurism

Pee kink done romantically! Haibara and Houjou are fooling around for the first time. Houjou tries to stop in the middle of it because he needs to pee but Hairbara won't let him go, telling him it will feel good if he holds it until he wets himself.

★ Special thanks to Regenbogenkind for the recommendation

Peeing during sex (uke)
Bara


Two men wrestle before the gods to win one granted wish-- however, it's revealed to win the other must make the other ejaculate first. The other rule is that they both must be coated in oil. At one point it appears that Ryuunosuke loses, but it turns out he just peed.

Desperation, peeing during sex (uke), urolagnia

Levi and Eren fall asleep after sex with Levi still inside Eren. Eren wakes up and has to go the bathroom. Levi won't pull out, but carries him to the bathroom, then tells him to pee while they're having sex. Afterwards, Levi suggests that he wants to pee inside Eren, but the story ends before finding out if he follows through.

Ch. 3 - Catheterization with peeing, peeing during sex (uke), urethral stimulation, voyeurism
BDSM
Incest (brother/brother)

Seme inserts a catheter, which also faintly vibrates, into the uke's urethra which causes uke to pee uncontrollably during sex.

Peeing during sex (uke)

Haru squirts pee continuously while having sex.

★ Special thanks to TooDeepInThisShit for the recommendation

Desperation, exhibitionism, peeing during sex (seme- in uke's ass), urolagnia, voyeurism,
Shotacon

Rin becomes aroused knowing Haruka is listening to him pee, then becomes erect when Haruka takes hold of his penis to help him aim while he pees. Later, while having sex, Haruka who is desperate to pee, loses bladder control and pees inside Rin. After he finishes, he pulls out and it flows out of Rin and onto the bed.

Peeing during sex (uke)
My Reading Manga website

Makoto has marathon sex with Haru and makes him come so many times that he finally loses control and squirts pee.