[Guido]

Episode 14 presented a new twist at the end at starting the halfway run for this series.

Spoiler for Furuichi:

Furuichi was a jerk but not a bastard after all.

He simply was jealous and resented to stand beneath Akiyuki's shadow for his love towards Haru.

Still, his various transformed faces were bizarre and oddities more so in comparison to the Humanforms or the Xam'd.

His face did not change to that of a Xam'd, and he was able to resist turning into stone after being badly beaten by Xam'd Akiyuki.

As Nakiami explained, his hatred was fed upon the Hiruko which kept him from becoming into stone. Now for not being able to change his face, then what I theorize is that he never fully accepted his existence as a Xam'd due to being dazzled by the light of his love towards Haru. (Yeah, I know. That's a corny way to put it)

Spoiler for Kakisu:

I'm sure that Kakisu learned of Furuichi's Xam'd condition for some while ago.

This was likely shown by the medical examinations. Otherwise, he would have ordered Haru be followed and tailed immediately to her rendezous with Akiyuki at the graveyard.

If he commanded the ASP to wait and hold off once Haru, Furuichi, and Akiyuki converged at the same rendezvous point, maybe it was for him to witness the power of two Xam'd fighting each other.

But, still we have to take into account the life debt that Kakisu owes to Dr. Takehara, which could be another reason why the commander ordered to have Akiyuki's life spared along with Haru and Furuichi too, although Kakisu clearly stated that he no longer viewed the two boys as people but rather as things.

Spoiler for Akiyuki:

It made for a creative twist in the storyline to have Akiyuki losing his memories with only the Xam'd face on.