Her official title is "Chief Engineer of the KOS-MOS Project General Operation System Research Center, Vector Industries First R&D Division".

[8] She has a bright, cheerful personality and is ever the optimist, perhaps to hide the scars of losing both her parents as a child and her fiancé two years ago.

In Episode I, it was revealed that she suffers from astraphobia, the result of two traumatic incidents which happened during lightning storms;[9][10][11] losing her parents and later her fiancé, Kevin.

Shion ends up being swept, along with KOS-MOS and her co-worker Allen Ridgeley, into a conspiracy concerning the very fate of mankind itself.

In addition to her intellect (a key factor in her usage of nanotechnology), she learned the same martial arts that Jin and Margulis are masters of as taught by her grandfather.

During the Gnosis' assault on the Woglinde, she was caught in close proximity to an FAE (fuel air explosion), which no ordinary human could possibly survive.

[15] Had U-DO not chosen to let humanity live on, Shion would have ultimately died due to the extreme stress caused by these communications.

She has also experienced several unusual perceptions, seeing visions of the young girl named "Nephilim" and of her deceased Realian nanny Febronia.

[16] It is also revealed in Xenosaga I & II and the database of III that she has the natural ability to see into the "Realm of Imaginary Numbers", where the Gnosis hail from.

Her consciousness has existed since the time of Lost Jerusalem as the maiden and close acquaintance of Mary Magdalene; her brief vision of the distant past was not through KOS-MOS' memory, but through her own.

Because Allen differs from Kevin in every conceivable way, including attitude, disposition, and personal history, Shion felt as though he would be the one able to offer comfort for her sorrowful heart.

Thus begins Shion's journey to Lost Jerusalem, wherein humanity's collective consciousness awaits guidance and salvation.