Actually...it probably is a cel. 

This is one of several beautiful images, proported 
to be designed by Kajishima (Tenchi's original 
designer)as 'teasers' for his version of the third 
OAV and/or his "True Tenchi" novels. It has been 
used in magazines along with (to keep it cel 
related) Ryochan's beautiful Goddess Washu Hanken 
cel.
So actually it is a Hanken cel, no doubt. But a 
reallly expensive one if it ever shows up!

It is anyones guess what it really means, but if 
he was to do a third OAV (unlikely) this may be a 
version of Ryoko that we would see. She is wearing 
Tenchi's coat, which you can't quite make out in 
your picture. (grin)

The baby may be assumed to be her's and Tenchi's, 
or Ryoko as a baby... but who knows. 
I prefer to think it is 'their' baby. :-)

I love that picture,
Kathleen