Kenichi: The Mightiest Disciple: The Attack of Darkness
Shijou Saikyou no Deshi Kenichi OVA · 史上最強の弟子 ケンイチ OVA
Synopsis
OVAs of History's Strongest Disciple Kenichi bundled with volumes 46, 47, 49, 53, 54, 55, & 56 of the manga.
Studios: Brain's Base, Shogakukan-Shueisha Productions
Source: MANGA