Here is what the seller wrote in an email :

When I lived in Japan, I have one student.
His father worked in Square Soft co.jp.
At the graduate time, my student gave me some 
pictures.
He said that they are drawing pictures by Akira 
Toriyama.
Akira drew these, then he asked assistant to draw 
cell pictures.
Akira suggest this way........
" This picture will be *** cell pictures".
Then his assistant will draw cell picture from 
this.
My student said that they re an original pictures.

These are draw on papers.

My student said that these are very rare, 
valuable pictures.
But I 'me not sure because I am so amateur about 
animation.

Here is a larger image :