User blog comment:Xilinoc/Ch. 648 - THE THEATRE SUICIDE SCENE 2/@comment-8179648-20151022115152

you know in my opinion I think Shunsui's zanpakuto fits his philosophy of "In battle both sides are evil" in an odd sort of way. His shikai is subtly evil covered up in the form of children games while his bankai is dramatically so.... kinda fits with the ninja and courtesan theme of his spirits (Muramasa arc is practically canon considering Tite Kubo design the spirits)...if i follow my theory on the zanpakuto representing one shikai and one bankai each.

His zanpakuto as a whole also seem to represent a tragic love story with childhood friends that played together as kids (his shikai), whom then fell in love as adults that were forbidden to be together and ended up commiting suicide (his bankai). Kind of fits his somewhat dramatic personality at least. Though if my theory is right it would be kinda creepy considering who Tite Kubo put against him... considering the lover parts seem to be played by him and his enemies.