Apologies for the poor quality. im not very good at drawing. <_>
anyway, the base of the of the chair would be a dark grey stone type color with the V and 5 symbol being a bright neon blue as they appear in the microsite. The two 5's on the side would float up and down and/or slowly rotate around the Y axis and would slowly pulse between a dark neon red and bright neon blue. The "Happy 5th Job" would sit statically above the chair and be a similar neon blue (though I'm open to having them either float or show up when you first sit and then fade away). The character would either sit hunched over, holding their head up with one hand and gentle neon blue light would emanate from their eyes (similar to the trailer pictures) or they would be learning against one armrest or the other with the similar neon blue light.
Story-wise, it would have been created by the Job Trainers, using the same technology that enabled the advancement to 5th job, for the player as congratulations for their time and dedication they committed in order to reach 5th job.