No Longer Human

No Longer Human (人間失格,) is the ability of Osamu Dazai.

Description
The ability annuls the skills of anyone he touches. Furthermore, the ability relies on skin contact and is always active. As such, he can nullify any ability even while restrained as soon and as long as it touches him. Due to this specific condition, the ability also apparently nullifies Akiko Yosano's healing ability; hence, Dazai requires the standard medical procedure or operation whenever he gets injured, unlike his fellow Armed Detective Agency members whom Yosano typically heals using her ability.

Dazai considers No Longer Human to be absolutely effective on any ability, so it cannot nullify any form of power that is not considered an "ability". As a result, Dazai cannot nullify Ranpo Edogawa's deduction skill and Howard Phillips Lovecraft's eldritch form, both of which are therefore not considered as abilities.

Thus far, Dazai has been shown to have nullified the following abilities:
 * Upon the Tainted Sorrow
 * Unnamed number ability
 * Beast Beneath the Moonlight
 * Rashomon
 * Dogra Magra

Appearances
{{Ability Appearance
 * Chapters=

Armed Detective Agency vs. Port Mafia Arc

 * Chapter 1 - Looking the Gift Tiger in the Mouth
 * Chapter 4 - Yokohama Gangster Paradise, Part 2
 * Chapter 9 - Beauty, Hushed Like a Statue

The Guild Arc

 * Chapter 19 - The Three-Way Battle
 * Chapter 25 - Q
 * Chapter 29 - Even If My Head Be Mistaken
 * Chapter 31 - The Twin Darkness
 * -|Episodes=

Armed Detective Agency vs. Port Mafia Arc

 * Episode 1 - Fortune is Unpredictable and Mutable
 * Episode 3 - Yokohama Gangster Paradise
 * Episode 9 - The Beauty is Quiet Like a Stone Statue

Azure Messenger Arc

 * Episode 7 - Love for the Disease Called Ideals

The Guild Arc

 * Episode 17 - Three Companies Conflict
 * Episode 19 - Will of Tycoon
 * Episode 20 - Though the Mind May be Wrong
 * Episode 21 - Double Black

Fifteen Arc
}}
 * Episode 26 - Dazai, Chūya, Fifteen Years Old

Derivation
The ability is based on the real-life Osamu Dazai's novel entitled No Longer Human (人間失格,), which tells the tale of Yōzō Ōba, a troubled man incapable of revealing his true self to others out of his detachment and fear toward human interactions, hence deeming himself disqualified from being human. He instead maintains a facade of hollow jocularity, but his alienation remains despite his efforts to alleviate his internal suffering. Within three memoranda that chronicle his early childhood through adulthood, Yōzō writes about life's casual cruelties, as well as its ephemeral moments of human connection and tenderness.