Ryuji Maesaka, a 21-year-old member of the Sunset Ravens clan, possesses long blonde or light brown hair. He dons a skull mask and black bulletproof gear, including a shirt and trench coat, for combat. His initial drive was revenge against Wang and the Eighth clan for murdering his younger brother before his eyes. This motivation fueled his reluctance towards temporary alliances, such as during the Shibuya Treasure Hunt event, until learning of Eighth's participation.

Following collaboration with Kaname Sudō and others during the Treasure Hunt, he permanently joined the Sunset Ravens. His goals evolved towards ending Darwin's Game entirely. Maesaka maintains a generally friendly demeanor towards clan members, assisting when needed, though he exhibits caution around individuals like Liu Xuelan. He strictly adheres to a personal code of repaying favors, acknowledging help received from figures like Hiiragi Ichirou.

His Sigil, "Truth or Lie," functions as a lie detection ability identifying deliberate falsehoods. It cannot discern if the speaker believes the statement true or is simply ignorant. Initially disliking this non-combat power, he privately termed it a "BS Detector." To compensate, he relies on conventional weaponry and extensive protective equipment. His primary weapon is an RPD light machine gun, supplemented by a concealed handgun. He owns an armored Humvee utilized for clan operations. His combat record stands at 19 victories out of 27 battles as of chapter 31. Additional personal details include a birthday on October 23 and blood type O.