I think this has been my favorite book so far in the series. Unlike volume 1 and volume 2, this one pretty much captured my interest from the beginning rather than getting more intriguing as I got deeper into the story.
We finally find out Yō’s full reasoning behind his actions at Deadman Wonderland--his sister, Minatsuki, who also happens to be a deadman (supposedly unbeknowst to Yō). Minatsuki gives Ganta a sob story about why she’s there, saying that she’d accidentally killed her abusive father. Ganta falls for it and decides that’s going to help her escape, only to be thwarted. He learns that Minatsuki is his next opponent in the carnival where we learn that Minastuki is a big ol’ lying freak who gets off on seeing other people sad or concerned.
In short: Yō is reunited with his sister and finds out what kind of monster she is while she uses him as a human shield. Crow starts giving calling Ganta’s projectiles the “Ganta Gun.” And, of course, Ganta wins the fight despite it all.
After the fight, Ganta meets another group of deadmen who want him to join their organization to take down Wonderland. To prove that he can trust them, they rig the event the loser (Minatsuki) has to go through so that she only loses some hair. They’re confronted by some overpowered Rock Monk that Shiro pretty much obliterates.
And the best thing happened. Ganta remembered his friendship with Shiro, and it was like the sweetest thing because Ganta seemed so genuinely happy as he remembered all the times Shiro saved/protected him not unlike she’d done when he first arrived Wonderland, even though Yō is terrified to death of her and calls her the real monster (in his mind). Which he may be right? As it seems that Shiro is the Red Man who killed all Ganta’s friends. We’ll see.
I think showing these different relationships is what really made this one for me. Even after Yō learns the truth, he continues to care about his sister. Now, they could’ve shunned Minatsuki, but both Ganta and Yō seem to be concerned with her well-being. Or at least, Ganta didn't want to see her maimed in any event. And it’ll be interesting to see how this new faction in Wonderland pans out.