The Carved Seal of Xephon

Ishiki plans to destroy the barrier around Tokyo Jupiter. Souichi is planning on tricking him somehow.
Ayato finds out from Itsuki that Haruka is in love with him, and is hurt that he didn't even know and he's been avoiding her.
Mamoru has been going through Ayato's stuff and has found out that he's close to Megu by listening to his cell phone message. He spends more time with her. He also finds Hiroko's diary, with the blue blood and the good-bye message. Later, he walks outside with Megumi. Ayato finds them. Mamoru grabs Megu around the neck and says that Ayato killed Hiroko, even though he knew she loved him. He says that Ayato will have to make a choice soon, and he will no longer be human. He punches Megu in the face.

Next episode

S01E22 - Operation Jupiter Obliteration