Kimetsu no Yaiba: a Adventure tale: part 1

the story begins with Takashi "Shiro" Shirogane, a 24-year-old young man who falling into a well in a abandoned shrine after his boyfriend, Adam was missing, falling an argument. He is magically transported to a land named Altea, a dimension surrounded by magical creatures called daemons, where he meets the half daemon named Keith who helps him try to adapt in this world and protect the quintessence Crystal that was embedded in his right arm while discovering the first true love of his life and finding things that are important to him as well as trying to defend the planet, while Keith on the other hand, is dealing with a betrayal that seals him to a tree for the years to come and the lost of his lover. Because of that he's planning to become a full deamon in order to defeat the Galra Empire.