That Time I Got Reincarnated as Slime Vol. 15

Following a fierce battle against his sister Velgrynd, Rimurus steadfast ally Veldora has fallen into the enemys clutches. An enraged Rimuru gives the order to massacre his foes, a request his Tempest top brass couldnt be more thrilled to oblige. Once Rimurus demon underlings evolve en masse, the final battle between Tempest and the Eastern Empire will begin in earnest. But if Rimuru wants to save Veldora, hell need to undergo an evolution of his own. Its time to unleash the power hes been holding back! | Fuse That Time I Got Reincarnated as a Slime, Vol. 15 (light novel)