Mitsuki and Sekiei

The wounds Mitsuki dealt Kū force the fake to withdraw for treatment, but Sekiei blocks Boruto's pursuit with Explosive Clay. Mitsuki urges Boruto and Sarada to chase Kū while he handles the enraged Sekiei, though Kirara pens the two in with a swarm of Akuta. As Mitsuki tries to talk Sekiei out of a fight that will only hasten his collapse, Sekiei attacks anyway, spitting the accusation that Mitsuki only pretended to be his friend. Boruto and Sarada smash several Akuta, whose bodies start to fail as well, and Kirara answers by unleashing a colossal one to crush them.

Boruto summons Garaga to tackle the giant Akuta, while Sarada baits Kirara with a Sharingan genjutsu and lands a Lightning Release strike. Kirara begs the giant to save her, yet Garaga squeezes it apart, and a falling chunk crushes her instead. Sekiei finally provokes Mitsuki into fighting back by threatening Boruto's life, and Mitsuki neutralizes the Explosive Clay with his own lightning. Elsewhere Sekki catches Ōnoki slipping away, sent along by Akatsuchi, and Kū reaches the doctor only to find the donors gone, resolving to take the physician's heart. Too far broken to be moved, Sekiei reflects on all he shares with and differs from Mitsuki, then dies, while Kurotsuchi rallies Iwa's shinobi to reclaim their village.

The episode is part of the Mitsuki's Disappearance Arc in the Boruto anime. It first aired in Japan on January 20, 2019, with the English broadcast on October 13, 2020. Mitsuki eventually rejoins Boruto and Sarada in the Old City, where they discover Kū restored with a new heart. The opening theme is Lonely Go! and the ending theme is Tsuyogari LOSER.