Ryuunosuke Akutagawa is a prominent antagonist in the anime and manga series 'Bungou Stray Dogs.' He is a member of the Port Mafia and is known for his ruthless and cold nature. Akutagawa possesses the powerful Ability 'Rashomon,' which allows him to manipulate his black cloak into destructive forms. Driven by a desire to gain recognition from his mentor, Dazai Osamu, Akutagawa is relentless in his pursuit of strength and acknowledgment. His complex character adds depth to the series' exploration of morality and ambition.