Eishirō Sugata, president of Sorami High School's New World Discovery Club, dedicates himself to researching the enigmatic "New World" and Synapse's Angeloids. He maintains a perpetually calm, neutral demeanor and wears only his school uniform, residing in a riverside tent that reflects his eccentric, exploration-driven life. Hailing from a prominent political family as the second son, Sugata deeply admired his older brother, sharing his passion for flight and gliders. A tragic argument led Sugata to perform a subpar inspection of his brother's glider; the wing failed mid-test flight, causing his brother's death. Accepting blame, Sugata was disowned, leaving his younger brother Yuugo as heir. This event fuels his quest for atonement through discovering his own "New World," prompting the club's founding. Intellectually gifted, Sugata specializes in analyzing advanced Synapse technology with Nymph's assistance and collaborates with Daedalus during Synapse visits. His research often involves high-risk experiments, sometimes causing unintended consequences. Though lacking supernatural powers, he possesses formidable combat skills, matching his childhood friend Mikako Satsukitane and surviving wildlife encounters. He shares a complex relationship with Mikako; her family servants call him "young master," but he finds her persistent romantic advances irritating. Sugata plays a pivotal role in investigating Synapse and Angeloids. He provides critical exposition through philosophical monologues referencing historical explorers, often foreshadowing events. His analytical skills aid the group, such as identifying Hiyori Kazane as an Angeloid before his memories of her are erased after her death. In the climax, he infiltrates Synapse to reprogram the Rule Obelisk, sacrificing himself during the process. Tomoki Sakurai's later wish resets reality, restoring him. His character extends beyond the main series. In the spin-off "Yūryō Bukken Mō Dame Sō," Sugata contacts Yuugo after recognizing Hamuel's resemblance to a deceased childhood friend, confirming their familial connection and his awareness of Synapse's secrets. He also appears in "Mahou Tenshi Cosmos," contributing to its storyline. Sugata occasionally engages in perverted antics, notably assisting Tomoki in measuring female characters' body sizes. Mikako describes him as "creepy, perverted beyond belief, weird beyond comprehension," yet acknowledges his reliability. His development shows a shift from solitary exploration to valuing friendships, particularly with Tomoki, who helps him move past his desire for world destruction.