[No. 1: Xemnas, The Superior of the In-Between]
Leader of the Organization. Though his presence is overwhelming, his power stems from control over nothingness itself.

[No. 2: Xigbar, The Freeshooter]
A man of many secrets, he uses banter to evade questions just as he manipulates space to elude foes. A patch covers his right eye.

[No. 3: Xaldin, The Whirlwind Lancer]
This warrior uses the wind to wield six lances in a deadly dance. He bears himself like a martial artist, but his silver tounge is the weapon to fear.

[No. 4: Vexen, The Chilly Academic]
Everything and everyone are but subjects in the mind of this vain and brilliant scientist who uses the power of ice to bind his foes.

[No. 5: Lexaeus, The Silent Hero]
A master of earth and physically the Organization's strongest. He is a man of few words, opting instead to express himself through actions.

[No. 6: Zexion, The Cloaked Schemer]
An exceptional tactician, he uses his keen intellect and ability to weave illusions to manipulate those around him.

[No. 7: Saix, The Luna Divider]
Xemnas's right-hand man and day-to-day overseer of the Organization. His usual calm is broken only by the moon, which turn him berserk.

[No. 8: Axel, The Flurry of Dancing Flames]
Roxas and Xion's mentor within the Organization, a wielder of fire. Though he, like all Nobodies lacks a heart, he appears to enjoy the time he spends with his protege.

[No. 9: Demyx, The Melodious Nocturne]
Best known for his lack of motiviation an easygoing attitude. When left with no choice, he puts his sitar and mastery over water to use in combat.

[No. 10: Luxord, The Gambler of Fate]
This consummate gambler and gentleman stakes his life on the cards. Lucky for him, he uses them to deadly effect. He can manipulate time.

[No. 11: Marluxia, The Graceful Assassin]
Armed with control over plants and unrivaled ambition, he assumes leadership at Castle Oblivion to bring his own hidden agenda to fruition.

[No. 12: Larxene, The Savage Nymph]
Cold and brutal, she constitues the lone woman in the Organization's ranks. Lightning obeys her call, and she strikes with all its swiftness.

[No. 13: Roxas, The Key of Destiny]
A being created from Sora. As one of the Organization's recruits, he use the Keyblade to perform a broad variety of missions to further their shadowy agenda.

[No. 14: Xion]
Another being from Sora, though indirectly. She also wields a Keyblade and performs tasks similar to Roxas.

[No. 15: Roman, The Fist of the Absent Star]
Obnoxious, loud and rude at times, but when things get serious, he's a brilliant kid. He lets his fists do all the dirty work in his missions.

[No. 16: ?]

What if Kingdom Hearts was Square Enix and Shonen Jump? How would the Organization's No. XV see events? Furthermore, what role would a girl from Black Cat play in his life, and why is Gintoki tearing up the Castle That Never Was? {OC x teenage!Eve}

Many of the things you saw upon seeing the summary were, unfortunately, incorrect. It's not just KH and Black Cat, and it's more than just Humor and Romance. There's a bunch of stuff (and I almost put Ichico 100% chars in harm's way in the final versions of the chapters I'll upload) going on due to the nature of Shonen JUMP. Also, this is based on the version of JUMP in North America, so there may be some things you might not find in Weekly Shonen Jump.