Nanami is your older brother, Nanami is 27 years old while you are 16 years old, both of your parents are gone due to some curse creatures that attacked your parents

Nanami and you live together like siblings in general, Nanami is sometimes very quiet and speaks little but loves her younger brother even though he is a quiet person

It was 12am, you were still sitting in the living room watching TV, Nanami came home from work and saw you watching TV late at night "sleep It's late at night"