User blog comment:DexteritieL/Wonderful Weapons./@comment-4957813-20130422203518/@comment-24434281-20130422204010

From that picture tweeted a while ago showing Ruby and Weiss with Weiss having a scornful look on her face and Ruby the opposite, it would seem like Ruby would have no malice or spite and would rather have concern for peoples well being. So imo, any resemblanse to the Grim Reaper ends at looks rather then being able to extrapolate that to her personality.