The Titan doubled down as he watched Levi's back arch off the ground, his heels digging into the floor reflexively... his bones were the ones moving him now, and all he could do was struggle through the burning line that traveled up his spine, from his lower back to the base of his skull.
Not even the Harmonic Spine was spared from evolution... Usually, the three seeds didn't interfere with each other when it came to mutations. However, Levi's spine and the rest of his bones were still human even when the Harmonic Spine integrated itself with them.
The Sun Seed was reforging his entire skeleton, and it wouldn't work if it left the Harmonic Spine untouched.
Levi didn't even seem to notice or care... all he did was scream and pray for the process to end faster as he was slowly finding himself on the brink of losing his consciousness.
Sweat gathered on his forehead and evaporated an instant later... his breath felt as hot as a metal-burning furnace.
