For all we know those who inherit the name 'Kenpachi' can be very similar, personality-wise, especially since it seems like the 11st Squad has always been known to be the 'Take No Prisoners, Bad Mother****ers' squad.
'Kenpachi' is the title of the strongest warrior (aka Captain of Squad 11), so it's not necessary Zaraki Kenpachi.
Hachi is most likely the Vice Captain of Squad 4, with Frog Girl the VC of Kensei's squad, which is probably 10.
After stopping around episode 5, I decided to re-download and re-watch Ghost Hound up to the current Genjo episode. They need to hurry up!
I'm currently in the process of 'acquiring' all of Spice and Wolf as well, and I've already got all 26 episodes of Denno Coil waiting for me to marathon...
It's really nothing like TMoHS.
And the Yaoi/shojo stuff is all in good fun. The show isn't seriously at all, which is good. The only thing is that you have to manage to sit through the opening, which is a task in and of itself.