He was very physically abusive to Shera. He even warned Shera that he will hit her for refusing him, right in front of Diablo. He was smug, arrogant, cocky, petty and cruel, quick to anger, abused his subordinates and his sister to the point of attempted rape, and threatens all-out war over the smallest slight, real or imagined. He was incredibly racist against every other race. He spoke in polite terms, but his tone was condescending, arrogant and petty. When he had Shera at his mercy, he loves to boast about how their elder brother "died in a hunting accident" thus, in his mind, making Shera his slave instead. He was convinced that he's the smartest and mightiest being in the world, and will happily boast it to anyone and everyone. When he was directly challenged, however, he was very quick to run and hide behind someone or something, even summoning the Force Hydra at the first opportunity, and yelling at it to attack Diablo, despite clearly not being able to control it in any way. When Diablo, Rem, and Alicia called him out on siccing a slime on Shera, before intending to rape her, he retorted that using the slime that way is foreplay and he believed it. When Diablo used his authority as Shera's "master" to compel Shera to profess how she truly feels, and Shera goes on to condemn the act, Keera loses what little sanity he had. His behavior as he was called out on his crimes is precisely like a spoiled child getting his toys taken away when his parents have had enough. He called everyone he comes across "stupid," especially when they are of another race, don't agree with his mindset, or both. He genuinely believed the world revolved around him. When he realized it didn't, thanks to Diablo completely crushing his defenses, taking Shera back, overcoming her brainwashing, and Alicia repeatedly pointing out that Keera's actions are violations of international law... He not only vastly overestimates his abilities, but looks down on everyone, and thinks they're idiots for not agreeing with his agenda. He called his father "feeble" for being reluctant to lead an invasion to take Shera back by force and loathes his elder brother for treating both Shera and himself kindly. There's also the fact that he calls Diablo and the guards of Faltra "idiots" for not abusing Rem and Shera's slavery collars and allowing the elves to pass the border checkpoint without incident, respectively.