Frieren/Relationships

Flamme
Flamme was like a mother for her. She saved her from demons and became her mentor. The first time she met Frieren, she praised her for standing her ground against and defeating a horde of powerful demons, but at the same time told her that it would have been smarter to just run away and hide or resort to ambushes. She was also the one who taught Frieren to hide her mana output so that demons underestimate her and get caught off guard, fully aware that it's seen as dirty and cowardly.

Flamme raised a young Frieren until she died of old age. Frieren cared deeply about Flamme, and is melancholic at the fact she is one of the only beings alive that remembers Flamme as anything but a legend. Einsam would take the form of Flamme in order to try to deceive Frieren.

Heiter
Frieren calls him "Corrupt Priest". They were comrades in the Hero Party and became close on their subjugation quest to defeat the Demon King.

Later, he asks Frieren to help him translate a grimoire that might contain the secret to let him live forever or be resurrected, though he is fine with just having a little more time on earth. However, it's later revealed this was just a ploy to keep her around and have her train Fern until she could protect herself when he was gone, and subsequently, have Frieren take her under her wing when she's dead. Frieren refused to take Fern with her because she'd be a burden, so Heiter asks her to at least train Fern while she is translating the grimoire. Frieren notes that it seems like he is not afraid to die, but he admits that is just a mask he wears beneath his smiling appearance to show off. As seen in his final years where she lived with him, the two really do deeply care about each other.