User blog comment:Xilinoc/Ch. 648 - THE THEATRE SUICIDE SCENE 2/@comment-29183117-20151022145409

At first I didn't really know what the connection was between Shunsui's Shikai and Bankai, but after giving it some thought I have an idea.

His Shikai revolves around the games of a child. Simple enough. But now there's his Bankai. The child has become an adult, and has been introduced to the games that adults play: love, and war. 1st Act, the adult takes the damage one may experience from both love and war, damage that is almost never limited to a single person, hence how it hurts more than one person. 2nd Act, the adult is left sickened and wounded by love and war, and cannot even muster the strength to move from their bed. 3rd Act, the adult, overwhelmed by the pain they've endured from these adult "games", leaps into the water to end their pain. The child has become an adult, and has learned the harsh realities of such a life: there is love, but there is also war, and sickness, and depression, and ultimately death.

I realize I could be completely off with this, and it could be stretching it, but after thinking about it this is what I was able to come up with. I'm not saying this is what the connection is, but I'm putting it out there as a possibility.