ニエルブの実験で揺れ動いた人間界。 グラニュートになり果ててしまった酸賀との戦いに終止符が打たれ、ニエルブは意味深な一言を残しその場を去る。 絆斗はお菓子屋「ひだまり」の店主がショウマの叔父である事に辿り着き、悩んだ末にショウマにその事実を告げる。 自分の肉親が思ってもいない身近な相手だと知ったショウマは、どうするべきか悩み複雑な心境を抱く。 そんな中、ニエルブの実験の裏で糸を引いていたグラニュート界の大統領ボッカはリゼルと共に人間界に降り立ち、人間の世界を視察する。 初めて直接対峙するショウマ達は、その絶大な力を前にボッカの脅威を知ることになるのだった。
The human world was shaken by Nierve's experiment. The battle with Sanga, who had turned into Granite, came to an end, and Nierve left the place with a meaningful remark. Kizunato discovered that the owner of the sweets shop "Hidamari" was Shouma's uncle, and after much deliberation, he told Shouma the truth. Shouma, who found out that his own blood relative was someone closer than he had expected, was troubled by what he should do and had mixed feelings. Meanwhile, the Granite World's great Article, who was pulling the strings behind Nierve's experiment, confronted Shouma and his friends for the first time, and they came to understand the threat of Bocca in front of his immense power.
