Ryoji Kaji Jr.

Kaji is a thirteen-year-old boy who dresses in KREDIT field gear for his work outdoors. The nametag stitched to his suit was chosen from several handwritten samples penned by his own voice actor, Kōki Uchiyama, and the protective mask he carries takes its design from the one worn during Operation Yashiori in Shin Godzilla.

The boy meets strangers with open curiosity rather than caution. Introduced to Shinji, he remarks that he has never encountered an outsider before and immediately extends his hand, guessing the newcomer must be a fresh assistant. His respect for his mentor shows in how he addresses Kensuke, calling him Aida-sensei.

Kensuke brings Shinji along to one of KREDIT's outdoor laboratories, where experiments with Sealing Pillar technology are underway, specifically so the two can meet. Only afterward, at nightfall, does Kensuke explain the name: the boy really is the child of Misato and the elder Ryoji Kaji, though he has been told nothing about his parents. Misato chose that distance herself, doubting she could be a good mother and deciding instead to protect him from afar in her role leading WILLE. The two are later photographed together, smiling, at KREDIT's No. 102 Restoration Trial Site with Kensuke behind the camera. Production materials reveal he was labeled Shinji Kaji in early previsualization, tied to a discarded subplot in which a Village-3 matchmaker arranges a marriage between him and Rei.