Adam appears in (AE2 - Ch29)
His biotissue was used as one of the materials to make Eve-00, Eve Zail.
Speaking about Sion, "It's become to weak to even use its sword. We're instigating the Adam's blood in it. Sion is the daughter of Eve, that was created with Adam's tissues and core. Most of her human body is dead. She can't control Adams' blood..." Robert Nelson, (AE2 - Ch29)