Popular for Junjou Romantica, Shungiku's earlier works were more samurai romance/yaoi of this sort. Here we have a basic spoiled brat and his bodyguard developing feelings for one another.
by Yasha

From Blissful Sin:

Ever since he was a child, Prince Uriel has always dreamed of searching for the lost city of Rowadis rumored to be buried somewhere deep in the desert. One day, he manages to sneak out of his country to join an excavation party in the hopes of learning more about his beloved Rowadis. However, the barren land turns out to be a dangerous place for the prince and he is captured by the savage Seldira clan. Follow the adventures of the young prince as he gets tangled up with the handsome leader of the Seldira and unlocks the mysteries of the desert.

1) The Welcoming Fire
During the O-bon festival, the ghost of Fuyuki's grandmother's brother's lover comes to visit, mistaking him to his lover.

2) The Sea Roar
A son of a noble isn't allowed to go outside. Yearning for freedom, he falls in love with his sensei who can take him away to the ocean.

3) Delicious Family Affair
Keito comes to live with his father and brother after his mother passed away. (they were divorced) and father and brother must try their hardest to hide that they're gay! (and that they are attracted to their own son/brother!)

4) The Dragon Knight and the Prince
Prince loves the tale of the Dragon Knight told by his butler, and goes for an adventure. A cute prince x butler story.

5) Sinner's Kiss
After snatching a bag, Jan finds himself being thrown into jail - the bag was full of drugs! Jan soon becomes an offering to the “Blond Demon” Louis!

6) Angel's Kiss
Epilogue to Sinner's Kiss

A short love story. 

From Liquid Passion: 2 color page side story for the famous poetic short story "Under the cherry trees" written by Motojirou Kajii in the early 1900s.

The young pirate head Sakaki met the beautiful samurai Murou... Why did Murou have the other half of the treasure island map left by Sakaki's grandfather? Why did Murou keep to himself? Could Sakaki open Murou's closed heart? And how should he handle his best friend who loved him, Juurou?

1-3) A Lie & Coffee & Sweet Kiss / A Key & Confession: Part 1 & 2
When Kano, a cafe owner, was attacked by some hoodlums dispatched by a land shark; a secretive, shady character, Otowa came to his rescue! Since then, Otowa frequented Kano's cafe and kept the yakuza at bay. Kano was unaware of the danger he's in and started to look forward to Otowa's visit... Until an equally dangerous man lured Kano out of Otowa's protection, and all hell broke loose...!

4) Confuse Me Sweetly In Darkness
This is the story between Yazaki and Yoshino. It picks up where they left off in the first story and tells how they became a couple.

5) If I Could Feel The Hand
This is a oneshot about two coworkers' mutual love affair, Isuzu & Kaidou. Includes some fun on a train

6) A Mansion of Love
This is a oneshot about the love between a master and his servant, Shizuki & Aoi.

From Storm in Heaven: Koizumi Kanna is infatuated with the man who came to the restaurant she works at and ordered a burger with no onions. Little does she know, Toujou Ren is interested in her as well, but for a different reason. Kanna just so happens to be the mirror image of a woman he knew a very long time ago. It is for that reason that he saves her when she nearly dies in a car accident. But the life he gives Kanna is far different from the one she lived before, and she's not certain it's the kind she wants...

Two kids become friends, even though he has an incurable illness. One winter, he was told he wouldn't be able to live to the next spring and she...

1) Victory - Ai wa Kabu 2) Endless Game 3) Lesson on Love at First Sight 4) Blood Dream 5) The Summer Dream of Youth 6) The Adorable Straw Doll 7) White Christmas Eve

Note: With the exception of the fifth one-shot, the other stories listed below have little to no BL content.

- Venez Chez Moi
An interwoven set of mini-chapters that blend seamlessly together, enabling the reader to catch a brief glimpse of the lives of men with many and varied personalities and circumstances.

- World Market
An author earns a living writing mediocre stories with morally questionable content, drawing inspiration from the eclectic mix of people who surround him...and learns that he may be more talented than he imagined.

- Dancing in the Snow
A supernatural story featuring Minami, Ideizumi and Kuzuha from So wa Reirei no Yuki ni Mai.

(Note: All the oneshots featuring this trio are gathered in the first volume of Rere Shuushuutan, which then continues with new stories about their involvement in various supernatural mysteries)

- Inhale and Exhale
Two artistic rivals whose devotion to their work has caused their relationships with the outside world to crumble, unexpectedly find themselves united in a common goal when one falls ill.

- Overflowing Swimming Pool
A short sequel to one of the author's previous yaoi works, Afuresou na Pool. As a stand-alone, this chapter makes little sense - so read only if you're familiar with the original series.

Collection of oneshots

1-2) Unforgettable Night
Kasuma, a high school student, meets his "idol", the president of Watase corporation...

3) All I Want To Do Is Embrace You
Sanjo Izumi, 14 years old, is the seemingly cool and composed heir of the Sanjo corporation...

4) The Biker Who Couldn't Stop
Yuusuke has a thing for motorbikes...

5) Sweet Violin
Sakimoto has problems with his noisy neighbour.

6) The Night of the Siamese Fighting Fish
Traumatized years ago, Fujishiro is cold to his lover, a college professor.

7) Getting Close to You With the Sound of My Flute
Tooru's family is known for its flute playing, but he's horrible at it. Then this horned guy shows up and kisses him...

8) Bloodstained Hands
Aru is a young knight who despises killing. Setsuen is a brutal warrior whose bloodlust disgusts Aru, but he can't stop thinking about him.

The story of a young ninja who travels the land in search of new jutsu and ninpo skills.
Told in the unique, surreal style of famous mangaka Shigeru Sugiura.

From Attractive Fascinante:

Because of Lionel’s viscount status, Ms Elena wanted to get engaged with him. However, Lionel was always in love with his steward, Isaac. Before the day of engagement, Lionel asked Isaac to hold him. Isaac, who was also in love with Lionel, couldn’t reject him. When Ms Elena demanded Lionel’s explanation of breaking off the engagement, Isaac felt hurt when Lionel refused to acknowledge his existence. Will our lovers be true to their own feelings?
--

In this volume:

• Subete wa Anata no Oose no Mama ni (Obeying Your Every Command)
• Shinso no Hana (Treasured Flower)
• Ukiyo o Hanarete (To Leave This Transient World)
• Pet no Keiyaku (The Pet's Contract)
• Kimi to Iru Heya (Living with You)

Wild Rock takes place in a prehistoric setting.
The first story is about a boy, Yuuen, who is asked by his tribal chief father to seduce Emba (a great hunter and the next chief of the rival Lakeside clan) by pretending to be a female so that they can get more food. The other stories are in the same setting, but with different characters (including the fathers of both characters from the main story when they were young).

Since times of old, it has always been the law of natural order for subjects to obey the emperor. However, this time, not only does a powerful general defy the emperor by climbing up the royal emperor’s bed but also demands that the emperor bears his children!

From DramaQueen:
The Kingdom of Landa, once a proud country, is weakened by internal espionage and strife with its neighbors. In order to save the country, Linth Highwind Belc Landa IV, Crown Prince of Landa, returns to his country determined to bring about change. But missing from his plans is a man - the one man who had left behind the intrigue of the palace for the freedom of the sea.

General Sei- Landa’s legendary hero- now guards Landa from his command post on a naval ship. Unknown to the General, among the new ensigns on board is a young Prince who is secretly plotting his return to shore! As fate has it, the opportunity comes when the General saves Linth during a fierce battle. Using his gratitude as an excuse, the Prince confronts the General about his absence from home - but suddenly finds himself at the General’s mercy! How far will Linth go to bring Sei home? Can a battle weary soldier become a guardian angel?

Sakurai Aya's "Whisper Under the Roses" is a school story set in the early 20th century.