Kiba

Kiba is a member of the Hokuto Three Crows and a supporting antagonist in Kamen Rider Build.

Past
Syoukichi Mihara was originally a worker at Kazumi Sawatari's farm along with Masaru Ooyama and Syuuya Aikawa. When the Skywall Disaster made Kazumi's land infertile, Kazumi used his savings to continue providing for the three and their families. Eventually, after the Hokuto government made a pact with Faust, Kazumi volunteered himself for the Faust organization's experiments so he could continue to support his workers, becoming Kamen Rider Grease and a soldier of the Hokuto government.

Out of loyalty, Syoukichi, Masaru and Syuuya joined the Hokuto military as well and volunteered themselves to be converted into Hard Smash to aid Sawatari as the Hokuto Three Crows. Becoming the Owl Hard Smash, Syuuya was code-named "Kiba".

Hokuto-Touto War
After Prime Minister Yoshiko Tajimi declared war on Touto, Aoba and the other Crows were sent in to spearhead the invasion alongside Kazumi/Kamen Rider Grease. However, after Hokuto sent in all their troops to invade Touto, Seito took the opportunity to invade and occupy Hokuto, easily conquering the country. Kiba was later beaten and held hostage by the Washio brothers to lure out Kazumi. He was freed by Akaba while Grease fought off the Washio brothers, though was later wounded fatally when he sacrificed himself to protect Kazumi from one of their attacks. As he lay dying, Kiba gave Kazumi his dog tag and told him he'd be watching over him with Aoba before disintegrating into yellow smoke.