Lambert is a character from Lupin III: The First
He's an archaeologist and member of the Nazi Ahnenerbe, dedicated to uncovering ancient secrets that could empower the Third Reich. The group killed Laetitia's grandfather when she was just an infant, dead-set unlocking Bresson Diary and recovering the fabled Eclipse device for his Fuhrer. When her parents tried to flee, he killed them as well in a fatal car crash from which he saved the little girl who was still too young to know the depths of the plot surrounding her.
Lambert is a old guy. He’d get angry at Laetitia any time she spoke out, so she learned to bottle it up. She comes off as quiet and shy however given the opportunity she’s actually pretty bold.
Lambert was generally kind to her until she started to outshine him in brilliance and ability. He gaslight her hard into believing she wasn’t smart enough to get anywhere without him