What is the fine-grained topic of the following text: The listing notes that the next issue will feature the first part of an official 'scenario novel', a serialised story by the game's scenario writer Matsuno Izuru titled Sengoku Basara 4: Sanbee Souran ~Oushuu Ni Teru Hikari~ Zenpen ('Three '-bee' Mayhem ~The Future Which Shines On Oushuu~ Part 1'). Only return the topic.
Upcoming serialised story in Sengoku Basara 4 by Matsuno Izuru