Japanese for Retro-Sexual
Also a common nickname for people named Ryan trying to impress, and become the boyfriend of, a girl who goes by Mayu. (see Mayu) Also the nickname does mean it's definition in english see below.
Retro-Sexual is -
Metro-Sexual for people that don't like Metro Station.
Shimo- Ryan your so Metro-Sexual
Shimo and Mayu - Yeaahhh you can't deny it
Ryan- Yes I can, I'm not Metro-Sexual, I'm RETROSEXUAL! Although, I prefer Retorosekushiaru