It's Nami-swannnn!Who is that on the most recent chapter cover??

Ch. 571 Cover
If your talking about that crab-like creature behind her; it's not a character that's meant to be a part of the manga story, I guess you can call it a cover story character


I hope we get another cover arc story on what the other SH's are doing! 
I hate that stupid PX-Zero! The curtain is about to fall on this war and I was hoping that we at least get more insight on Kuma! Damn it!
))
all im saying is i would like to se him using it a bit