The Ideal Sponger Life manga volume 4 features story by Tsunehiko Watanabe and art by Neko Hinotsuki.

Two years have passed since Zenjiro was summoned to a kigdom in another world and married its beautiful queen. Now, Zenjiro and Queen Aura celebrate the birth of their child--the young First Prince of Capua--and the realm celebrates with them. Yet while Zenjiro is busy adjusting to his new life as a father, a bloody massacre breaks out along the vital Salt Road. A company of knights and warriors rides to do battle with all manner of wyverns, even as a delegation arrives from the Twin Kingdoms with an agenda all its own!