Reinhard van Astrea/Relationships

Theresia van Astrea
Theresia was possibly the dearest relative he ever had. Reinhard worried a lot about her and became discouraged when he heard that she died. Sometime later when the Witch Cult resurrected her, Reinhard killed her with ease because for him his grandmother was dead and that thing was a corpse, following into more conflicts with his grandfather Wilhelm.

Wilhelm van Astrea
Wilhelm's relationship with his grandson is very tense, likely because Reinhard inherited his wife's power as the sword saint just before she died, making her much weaker than she was at her prime. Nevertheless, Wilhelm did want to fix their relationship after the Hakugei was successfully killed. However, after Reinhard was forced to kill Theresia's resurrected corpse, Wilhelm asked his grandson if he had any regret doing so. After hearing Reinhard's answer, he begins calling the current Sword Saint by his full name, showing that he sees him now as a stranger rather than his grandson.

Natsuki Subaru
Subaru sees Reinhard as a reliable friend, even bragging to the Witch of Sins that he personally knows the current Sword Saint.

Felt
As a part of Felt's faction, Reinhard is willing to do everything in his power to make Felt the 42nd King of Lugnica.