The transformation of Hermione into a vampire. Galen blames himself and feeds her his blood, Takara has reasons to hate vampires and believes she has lost her best friend, while Hermione has to live with the struggle of what she is now and the temptation.
In the epilogue of the series, its shown that now Takara and Ciel have problems due to the fact that Takara has allowed Hermione to be with her and Galen. Since Ciel can't overlook her issues with vampires due to her tragic past, the two haven't been able to get along for some time now.
