Keera L. Greenwood is one of the antagonists of the series How Not to Summon a Demon Lord. He was a crown prince of the Kingdom of Greenwood (home nation of the elves). He was the abusive older brother of Shera L. Greenwood. He was Diablo's self proclaimed love rival.
He was voiced by Akira Ishida in the Japanese version, and by Stephen Fu in the English version.
Originally in the past, he was kind and respectful for his family. He loved his sister Shera dearly and protecting her. He was loyal to his father and his older brother.
Currently after his parents and older brother's deaths, Keera's personality changed to be cruel, psychotic and sadistic to even his own kind and family when considered his father as feeble. He is a very abusive and perverted towards his younger sister, Shera, as he tormented and raped her in his attempt of making her to force to engage in a marriage due to his harsh sister complex caused his sister to hate him. After Shera left, Keera has no qualm putting a bounty on Shera to capture her. He attempted to manipulate his own sister to deceive Diablo into loving her brother.
He is overconfident of his strength and viewed those as weak. He mocked Diablo of his sister, Shera. He hates Diablo for "taking" his sister away from him (but in reality, she ran away from him due to his cruelty).
After his summon was easily defeated by Diablo, Keera is also a coward who is afraid of Diablo's level 150 power level. After trying to escape, Keera was beheaded by Lieutenant General Chester Ray Galford.