It's difficult to say if they are common. There could be a lot of guys who have had such an experience but are too shy or afraid to talk about it. Also, society's view on same - sex activities can greatly influence how often these stories are shared or even occur. Some places are more progressive and might make it seem more prevalent, but overall it's a complex matter that involves personal, social, and cultural aspects.
Sharing such stories is highly inappropriate and disrespectful. Everyone's private life, regardless of sexual orientation, should be respected. Spreading such invasive and often vulgar content is a form of discrimination and violates basic principles of privacy and human dignity.
It depends on how we define'mom sleep sucking stories'. If we think about moms who breastfeed their babies at night and are often in a state between sleep and wakefulness while the baby is sucking, then it can be considered common. Moms are usually exhausted, and their bodies adjust to respond to the baby's needs even while they are sleepy. There are many such stories among new moms where they might not fully remember the details of the night feedings because they were so tired.
It's an extremely embarrassing situation. First, try to stay calm. Maybe quickly cover up and excuse yourself to get dressed. Then, later when things have calmed down a bit, you could have a talk with your mom about privacy and boundaries in a respectful way.
Yes, for instance, if a baby is breastfeeding discreetly with the help of a cover while mom is in a public place like a quiet corner of a coffee shop. This is a natural and positive story as breastfeeding is a normal part of a baby's nourishment, and moms are often able to do it in a way that respects public decency.
There should not be such inappropriate stories in proper literature. Most literature focuses on positive values, moral lessons, and healthy relationships. Such a disturbing concept goes against basic ethical and moral norms, so it is not likely to be a common theme in mainstream literature.