In terms of realism I think it's totally acceptable that she forgives her father so quickly. People who are often abused can exhibit overt amount of sympathy and forgiveness for their abuser especially in cases where the abuser provides for them.
That being said that dad should just rot if he...
I always like how the author portrays when Shia is embarrassed like when she said 'boo' and homeboy just stared at her. Usually in manga they don't go for subtle or realistic reactions like silent embarrassment quite in the same way as the author does.
On the other hand although I would support...