Transient; derived from the Latin phrase, Trans, meaning to move across. with the suffix it means one who moves. (if I'm not mistaken)
A fitting title, as the things important to him are fading... and moving on...
well, now I'm done being all Latin geek, I can not explain my intense like for this piece, everything from the color, to the expression one his face, is the essence of loss.
and you have captured it well.