Conan died in the duel with Gin, but he could not forget the feeling of falling in love with Gin.
When he woke up again, he found that he was a foreigner and had a younger brother named Harry Potter.
This is the story of Conan and Gin who died and were reborn in the HP world to help Harry defeat Voldemort.
This is also the story of Harry defeating seven little Voldemorts with the help of his brother Conan and falling in love with his beloved Potions Professor.