Both are romanian fighting game vampires who happen to be VERY stylish, valuing beauty, loving women and wearing fancy suits in battle, they also happen to be very wise and skilled due to their age (Demitri being 500 years old and Slayer being more than thousands years old). They both began as quite successful and influential men (Demitri is the master of Maximoff family and also straight up has his own castle, Zeltzereich, while Slayer was the original founder and leader of Assassin's Guild), however their success would quickly end (After a battle with Belial Aensland, Demitri would be exiled from Makai and would be sent to human world, while Slayer had to leave Assassin's Guild due to him losing interest in it), though they would return to once again re-enact their plans (Demitri challenging Morrigan, the daughter of Belial and Slayer wanting to fix Assassin's Guild, which has become a gang of murderers after he left). Both are regarded as some of the most powerful characters in their series (Demitri being the most powerful vampire in Darkstalkers and Slayer being the most powerful character in Guilty Gear). Both of them have opposite personalities (Demitri is very agressive and violent in combat, while Slayer tends to be very calm and even holds back in fights). Both also have completely opposite views on human lives (Demitri sees humans as an inferior race and food, while Slayer likes to observe humans, giving them advice and even finds drinking blood distasteful). They also have ties to pre-esxisting classical vampires (Demitri was born shortly after the defeat of Dracula, while Slayer is a descendant of Nosferatu).
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