Probably hard to notice because of the drawing style...
Marisa have the usual Deibu wife and Deibu ko-reimu, and a mistreated ko-marisa. One day the wife found out Marisa is cheating with an Alice and insult the ko-marisa.
Hearing she's unwanted, ko-Marisa run away from home and got adopted by a Patchouli family.
She grew up into the best hunter in the clan (this is not the father).
Then her family came at her, demanding food under the base of being "single mother", "I've raised you up" and "it's your duty as a child/older sister".
Marisa doesn't have any more love for them. She just leave them for her own family.
Father Marisa has already run away with Alice, leaving the Deibu.
The next day, Reimu attacked the food storage in chief Patchouli's home that's prepared for weak and disabled members. Reimu claimed she's "emotionally hurt" and thus entitled to eat all the food stock.
This Patchouli is Marisa's husband, and Marisa killed her own mother for being a trash. It's alright, she doesn't need two family
Ko-Reimu, left in the nest hole, cursed her mother for not bringing her food.