Anime Crossover: How Many Cheats Do You Have?

[Main fandoms: Bungo Stray Dogs, Detective Conan, Katekyo Hitman Reborn!] [Raising kids + max-level powerhouse + a hint of a harem + no romantic pairing in the ending] After arriving in Japan, Guanyue Li was bound to a system calling itself the "Yokohama Rescue System," System 0407. She saw right through its lies. In the end, System 0407 confessed everything: it was an ability-imbued object, the [Book]. The [Book] had accidentally broken through the barriers between worlds and seen glimpses of other parallel worlds. Its dearest [Bookmark] had somehow ended up in an orphanage, where it was bullied by a gloomy mushroom-haired director and a group of nasty kids. That alone was enough to make the [Book] furious. But then the Special Division for Unusual Powers went and lost one of its [Pages]?! The [Book] had had enough. It ran away. With information provided by the kind Vongola Rings, it found Guanyue Li, who had come to Japan for a vacation. After hearing what it had to say, Guanyue Li agreed without much hesitation. She loved adorable human children, especially those under ten. And so the future big family, currently a small one, welcomed its first little one: Nakajima Atsushi, with white hair and purple-and-gold heterochromia. A year later, a huge explosion brought the second little one into the family: Nakahara Chuuya, with orange hair and blue eyes. The first and second are here, so how far behind can the third be... At the [Book]'s urging, Guanyue Li also established a detective agency. But the agency was on the second floor, so, to make eavesdropping on gossip more convenient, she opened a convenience store on the ground floor. A Western-style restaurant, a clinic, a clothing store, a dessert shop... Guanyue Li: Retiring in Japan really was a great choice!