After Touya learned of summoning magic from Yumina Ernea Belfast, he summoned the Heavenly Beast that came out as white tiger. The Heavenly Beast was skeptical of Touya's capabilities decided to gauge his magic power which was overwhelming and left the former surprised. Impressed, the beast deemed Touya worthy of being its master and asked for him to name him to make the master and servant bond official. Touya gave him the name Kohaku which it immediately liked after Touya explained the name's meaning with this Kohaku officially became Touya's contracted beast. Kohaku soon asked to walk by Touya's side at all times and took on smaller form to look inconspicuous.