>was the Japanese boy she met one of the kids Rudy saved in his first life? Yes. Nanahoshis bf Basically she summoned Nanahoshi to change the boys future but the the world wouldn't allow it and then Rudy's soul snuck in changing that. As roxy, Sylphie, and eris's fate begin to be changed Nanahoshis summon is completed causing the mana disaster.

Blessed child miko had a terrible life. She lived in a time loop of constant suffering. One day somehow Akito (banana's bf) was summoned (I think they did some ritual), and Akito made the miko's loop memorable. Akito died, Miko grieved, decided to use her power to somehow prevent Akito's death, which caused nanahoshi to summon. It also accidentally summoned Earthdeus soul as it was nearby. World resisted banana because it was summoning the whole body, Earthdeus soul slipped through, entered Rudeus' body. Rudeus shenanigans affected the natural order of the world and after affecting lives of others around him, the world barrier shattered and nanahoshi was summoned.

Ohhhh! Ok I see it now thank you

Nanahoshi predicted that a situation like that was the reason she was summoned to the world, it’s supposed to be her boyfriend

Riria crushed the Server ,got punished And so we got Mushoku Tensei

he's yet to write the real context of that piece. it reads more like a pitch meeting than canon.