Ghost Jim

Elena has come back from vacation to find that her boss's home has burnt down, and he's already dead and buried. However, her boss is the brilliant scientist and inventor Jim, and she soon discovers that he is not as dead as she had feared. He had been performing an experiment to turn himself into a ghost, and succeeded in transferring his consciousness to a little metal robot. Their troubles are only beginning, though, since someone has stolen Jim's precious safe! That safe contained not only all of the data from Jim's research, but also the device to recharge Jim's new body. If Elena can't help him find it, his consciousness may truly vanish from the world!
(Source: tethysdust @ mangahelpers).