Isekai wa Smartphone to Tomo ni. 2

Touya Mochizuki has grown comfortable in the other world and is now engaged to Yumina, Yae, and the twins Linze and Elze, but relationships that once felt simple now carry responsibilities he has no idea how to manage. At the same time, the fairy Lean asks for his help locating the remaining pieces of Babylon, the floating facilities left behind by Professor Regina Babylon 5,000 years ago.

The search leads Touya to new installations and secrets tied to ancient technology while the mysterious Phrase continue threatening the world. As both his circle of fiancées and his influence expand, Touya finds himself changing from an adventurer who cleverly uses a smartphone into someone responsible for people, territory, and a future he never planned to inherit.