Yakuza Yaoi

Plot: Slutty uke boss essentially adopts a serious policeman into his group after the man was rejected from the force for attacking his father. Policeman falls in love with his masochistic boss, who thinks he can't love anyone 'normally'.
Hands down my favorite manga, across all genres, themes, etc. I will literally be late for work to read it if I find out it updated in the morning.
Attentive Seme X Masochistic Uke

Plot: Big Boss Daddy Seme is a leading man in the mafia and crosses paths with a street-dealing mechanic uke. He brings him under his wing and gives him work as a relationship develops between them.
Soooo gooooood omg...best part is how hunky the uke is and not just a complete idiot. It makes the relationship seem more realistic because both characters could actually be real.
Possessive Seme X Manly Uke

Plot: After escaping an abusive relationship, boxer uke runs into a yakuza who decides to adopt him as a lover.
This manga is so freakin good, the sex is positively delicious, but definitely not a vanilla relationship so enter at your own risk.
Possessive Seme X Manly Uke

Plot: The uke doctor saves a wounded yakuza, who (in his delirium) thinks his savior was a woman and searches for his rescuer.
The uke is the cute, defenseless type, but their romance is very charming. An oldie but goodie.

Plot: A young master uke comes across a yakuza bleeding out in the snow, and takes him in to nurse him back to health. The yakuza can't help but fall in love.
Well written and good pacing. Seme is sincere and honest, and the uke is kind-hearted and stubborn.

Plot: An outrageously flashy yakuza uka falls in love with a cop, who eventually just can't say no to him.
It's the type of story that just drags on and on and on, and it hasn't updated in a long time, but there's enough to read and most issues get resolved in a few chapters rather than having these huge cliffhangers. It borders more on cute and comedic, definitely not super moody.

Plot: Old classmates find that one has become a detective and the other a yakuza, and enter into an tentative agreement to pass along info (the agreement is sex).
This author has a ton of good stories in general. I like how their ukes are more manly yet still beautiful, and the couple are just genuinely in love with each other.
Puppy-Dog Seme X Serious Uke

Plot: (Chp1-3) The young master of a group is forced into acknowledging his inheritance when his older brother is killed. An older mentor teaches and guides him into the new role, and both fall in love.
Another goodie by this author, I find myself revisiting this story all the time.
Serious Seme X Young Master Uke