Bertille Blanc (ベルティーユ・ブラン Berutīyu Buran?), also known as Bell, is a main character and a heroine in Akiba's Trip Festa!. One day, she, a vampire girl, woke up from a coffin in Akihabara. Having lost her memory of the player, she decides to be participating in the "Festa" in order to regain the memory. She is a foreign synthister who saved Nanashi, the protagonist, from a his critical condition by enacting the blood contract which saved his life and altered his abilities.