This is a Pure Evil proposal of Issei Kurosaki.
It's because my last proposal was forgotten despite improving it. So, i decided to make another one to make sure it never been forgotten.
What's the work?
Kamen Rider Kabuto: God Speed Love (劇場版 仮面ライダーカブト GOD SPEED LOVE Gekijōban Kamen Raidā Kabuto Goddo Supido Rabu) is a Japanese sci-fi Tokusatsu movie directed by Hidenori Ishida and written by Shoji Yonemura that serves as a movie adaptation of Kamen Rider Kabuto. The movie was released on August 5, 2006 during the series run. The movie takes place on an alternate timeline seven years after the meteorite crashes into the Earth's oceans, bringing the chaos onto planet. In order to restore their planet, ZECT unaware that they may have responsible for it.
Who is he?
Issei Kurosaki (黒崎 一誠 Kurosaki Issei), known as Kamen Rider Caucasus (仮面ライダーコーカサス Kamen Raidā Kōkasasu), is a major antagonist in Kamen Rider Kabuto: God Speed Love. He transformed into Caucasus using the Caucasus Zecter.
What he has done?
Caucacus first appeared when Hercus is looking for Shura and killed him with Hyper Clock Up before leaving a blue rose onto his corpse. One day, Kurosaki was sent to space station ensure that the Jacob's Ladder plan went on.
After Kabuto and Gatack managed to get onto the space station to discovering ZECT's plan to have the Next-Worms invade the Earth, Caucasus confront them and overpowering them at first. He was about to kill Kabuto after revealing his true intentions. However, Gatack managed to hold him off which allowed Kabuto to steal the Hyper Zecter and sent him away to the space.
However, Caucasus somehow survived and tried to kill Kagami by breaking a pod window to suffocate him, but Kabuto managed to rewind the time using Hyper Clock Up to prevent his death. Kabuto then finished him off by using a Hyper Kick, which sent him flying to the meteor and dies before the missile hits and exploded.
Kurosaki does stands out as the most villain in Kamen Rider Kabuto alongside Masato Mishima. Different from other villains in the movie, while ZECT members, including Sou Yaguruma and Tetsuki Yamato, are only doing it to restore the Earth, Shura Hokuto redeemed herself after learning about ZECT's intentions, and the Worms were only Amoral monsters, Kurosaki did stand out amongst them due to his genocidal and cataclysmic intentions were more dangerous. However, the God Speed Love counterpart of Masato Mishima didn't stand out as his original counterpart.
Prior to the events of the movie, Kurosaki joined ZECT to ensure that Jacob's Ladder plan will be completed and the Next-Worms will invade the Earth. During his first debut, he killed Hidenari Oda/Kamen Rider Hercus in cold blood before leaving a blue rose on his corpse. When Kabuto and Gatack managed to get into the missile, Caucasus managed to overpowering them and taunted them for their effort to defeat him. He even boasting about his Darwinistic desire. After he was ejected away to the space, he attempted to kill Kagami by breaking the escape pod window and make him suffocated before Kabuto intervenes it.
While confronting Kabuto and Gatack, he claimed that he doesn't cared about humanity nor Worms, only cared for his own scheme to have the Next-Worms invade the Earth and the missile destroyed the humanity as long as he would satisfy his Darwinistic desire. Though he joined ZECT in order to make sure that the Jacob Ladder's plan went to be completed, it is unknown if he did showing his loyalty to them or doing it out of pragmatism. He also didn't cared if he would harmed others, as when he killed Hercus in cold blood and attempt to leave Kagami to die from suffocation in space.
I bet he qualifies.