Ryūichi Takeshima is Tokyo Esperion Youth B Team's center-back, wearing jersey number 27. Standing 171 cm tall and weighing 65 kg, he has blood type O and a birthday on October 11. Directly promoted from Esperion's Junior Youth academy, Takeshima specializes in defensive skills, forming a rare strength within the club's typically aggressive attacking tactical framework. On the field, he exhibits a calm, analytical approach, often explaining tactics to teammates like Ashito Aoi. Despite his outwardly reserved demeanor, Takeshima maintains a passionate commitment to his defensive role. His playing style prioritizes careful positioning and intelligent anticipation over physical aggression. His essential defensive coordination with fellow center-back Keiji Togashi involves navigating personal incompatibilities for the team's benefit. Takeshima's background reflects progression through Esperion's youth system. His relationship dynamics, particularly with Togashi, illustrate the team's emphasis on functional cooperation over personal rapport. Off-field personality traits remain largely unexplored.