Kensuke Aida lives as an adult in the post-Third Impact world, residing in the survivor settlement known as the Third Village. He serves the community as a self-described "jack-of-all-trades," essential to its operations. Toji Suzuhara dubs his expertise "survival otaku" skills, knowledge that proved vital for the group's endurance after the catastrophe, making Kensuke a respected and indispensable member.

He maintains a close, near-familial bond with Asuka Shikinami Langley. She stays in his home between deployments aboard the AAA Wunder, affectionately calling him "Ken-Ken," while he consistently addresses her formally as "Shikinami." Their relationship involves practical support like providing shelter and food, and extends to moments of care, such as covering her with a blanket when unclothed or cleaning up after Shinji Ikari becomes ill upon seeing her DSS choker. A significant flashback reveals parental undertones: Kensuke, dressed in a costume resembling Asuka's childhood doll, comforts a younger clone version by patting her head, fulfilling her expressed longing for parental affection.

Kensuke acts as a supportive figure for Shinji Ikari during Shinji's time in the village. He offers guidance drawn from his own experiences overcoming challenges and integrating into the community. Kensuke acknowledges Shinji's difficult relationship with Gendo Ikari and shares information about Ryoji Kaji's death and his namesake son. While visiting the grave of his own father, Hajime Aida, Kensuke advises Shinji to attempt communication with Gendo despite the difficulty, advice that ultimately steers Shinji's decision to seek reconciliation. Kensuke’s background includes the childhood loss of his mother and his father’s employment at NERV. His youthful fascination with military technology and intense desire to pilot an Evangelion informs his adult perspective, contrasting with his eventual role as a pragmatic survivor.