Vacher

In Genshin Impact, Vacher initially appears as 'Marcel', a merchant in Fontaine. However, his true identity is Vacher, an adventurer from Snezhnaya. Vacher was deeply in love with another adventurer named Vigneire, but during an underwater expedition, Vigneire tragically dissolved after coming into contact with the Primordial Sea water. Devastated by her death, Vacher became mentally unstable. In his attempt to revive Vigneire, he kidnapped women of similar age to her in Fontaine for his experiments. To conceal his actions, he took on the alias of Marcel, the merchant. Ultimately, his crimes were exposed, and he was brought to the Fountain of Lucine, where the consciousness of Vigneire, whom he had desperately tried to revive, appeared as an Oceanid, causing him to fall into despair and die. It's worth mentioning that the game's Vacher is based on the real-life French serial killer, Joseph Vacher, who was also known as 'The French Ripper'.