No, it is not at all appropriate. We should uphold good moral values in our communication and avoid promoting or spreading any form of vulgar or improper content. Society has standards of decency, and this clearly goes against them.
There could be tales of how the father teaches his little girls valuable life lessons, such as the importance of kindness. For example, he might show them how to help an old neighbor carry groceries, and through this, the girls learn to be empathetic.
Typically, it's the daddy who plays a crucial role, and his daughters, whether it's one daughter or multiple, are also central. The stories might focus on their relationship, so they are the key elements in these stories.
Yes, for example, a little girl who had a bad day at school. She sat on her daddy's lap when she got home. He held her close and let her cry. He then told her how much he loved her and that she was smart and strong, which made her feel better.
I'm not aware of any specific "huge cock in tiny mouth stories" in mainstream literature. Most literature focuses on more positive, moral, and diverse themes.
A great 'daddys that love daddys' story might be of two dads starting a business together. Along the way, they also supported each other in their relationship. They showed that they could be successful in business and also be loving partners. They made sure to set aside time for family dinners and outings, despite their busy work schedules.
Maybe there's a story where a little girl sits on her daddy's lap at a family gathering. They share a piece of cake and he tells her funny stories about when he was a kid. She giggles and feels so safe and loved in his arms.
One story could be a little girl sitting on her daddy's lap while he reads her a bedtime story. The warmth and safety she feels in his arms as he voices the characters from the book. It's a simple yet precious moment of bonding between father and daughter.