After the noble Kappa Kingdom falls to the Otter Empire, the Kappa prince Keppi loses much of his power and becomes helpless against the unseen Kapa-zombies. These zombies plague the world, and are the creations of the Otters and manifestations of people's deepest desires. With no other choice, Keppi must rely on three young boys: Kazuki Yasaka, who must carry a box with him wherever he goes; Enta Jinnai, Kazuki's childhood friend; and Tooi Kuji, a delinquent and a school truant.
By having the mythical organ called a shirikodama removed from them, the boys are able to become Kappa themselves and fight the Kapa-zombies. However, to defeat them, the boys must connect with each other via their minds, bodies, and—most importantly—secrets. As the Kappa Kingdom relies on these boys, they must reveal themselves as they have never done before, all the while learning that connections are fragile and truly precious things.
[Written by MAL Rewrite]+ More
Characters & Voice Actors

Jinnai, Enta
Main
Akutsu, Mabu
Supporting
Azuma, Sara
Supporting
Enta's Grandmother
Supporting
Hakoda, Osamaru
Supporting
Keppi
Supporting
Kuji, Chikai
Supporting
Nekoyama, Moukichi
SupportingRecommended for you
Panzer Dragoon
OVA
27m
Ni Zhuan Ci Yuan: AI Jue Qi
ONA
17m
Ninja Bugei-chou Pilot Film
Special
1m
Obake Zukan
TV
2m
Ogami Matsugorou
OVA
50m
Ore no Sora Keiji-hen
OVA
44m
Pachislo Kizoku Gin
TV
25m
[RAW] Rainbow Sentai Robin
TV
26m
Captain Kuppa
TV
25m
Saikyou Robot Daiouja
TV
24m
Gun Girls
ONA
14m
[RAW] Coji-Coji
TV
25m
Great Conquest: Romance of Three Kingdoms
Movie
148m
The Totem Warrior
ONA
15m
The Legend of Ancient Soul
ONA
15m