Ryoma's son Shiro wanders out of his Deeprealm, unaware of his royal lineage or the danger that awaits him.
How to Unlock
This Paralogue becomes available after Ryoma reaches support rank S with a female unit.
Rout the Enemy
The levels of the enemies in this battle will depend on your current levels and the chapter you are on.
Shiro starts as an ally unit, and Ryoma has to talk to him in order to turn him into a controllable unit. However, Shiro starts off rather far away. You can deal with this in various ways. For example, have Ryoma pair up with a flying unit and have them fly toward Shiro, then have Azura paired up with another flying unit to sing to Ryoma so that he can get a second turn to reach Shiro. Another option is to equip a unit with a Rescue rod and use a flying unit to get close enough to Shiro to use Rescue on him, after which Ryoma can talk to him.
Either way, once you recruit Shiro, you can have him use his Offspring Seal to become an advanced class. This is a good idea because he starts out at level 20 and can't earn more EXP until you reclass him.
You can use the Dragon Veins to turn the desert into plains, allowing your units to move more quickly.