This tag designates the male form of Roto, the hero and protagonist of Dragon Quest III. In the game, the player designates the character as either male or female. Originally, the sprite used was the same regardless of this choice. Use this tag when it is clear (e.g. by a notably masculine appearance, or the presence of well-defined sexual characteristics or activities) that the artist intended for this iteration of Roto to be male.
See the Roto wiki for further details on the character. This tag was proposed in forum topic #18888, see that thread for further suggestions on its usage.