Ban thinks of Shinwi as an adult, but Shinwi is still only 17.
From Ban's memories it seems he felt close to a younger child who was part of the experiemnts he to underwent and that Ray is using and in contact with the researchers.
Also get the feeling that Shinwi atachment to Ban may be because Shinwi was said child, but might have lost his memories after Ban escaped.
Something feels off about the wife, she is way to happy to see the younger brother who went no contact with her future husband..
Either they are playing matchmaker again..., she is the the i can fix it type or she knows somethingh we and MC dont.