Review Detail of BlueGummies in Nanomancer Reborn - I've Become A Snow Girl?

I really liked the story for the first few hundred chapters but after the love interest got introduced I felt like it just kind of got boring... The reason for this is Shiro 'merges' (for lack of a better word) with Kuromi and suddenly gets a bunch of memories. We don't know anything about these new memories and now a bunch of new characters are introduced and are now very close to her with her caring for them like family. I really can't feel any attachment to these characters who I don't know anything about and it feels kind of awkward. Especially the love interest, he doesn't seem to have any personality other than being OP. Another thing is the world-building, I don't really know much about the other people in the world. Like what is the average strength and how many people are there. It would be great if the author could describe things more.