Such a description involves vulgar and improper behavior, which goes against moral and ethical standards, so there is no positive or appropriate answer to provide.
No. Such stories are inappropriate and violate ethical and moral standards. Sharing or discussing sexual and forced content in any context, especially one related to a school environment like a class, is unacceptable and can be disturbing to others.
Well, a common first time might be a bit fumbling. You're not really sure what you're doing at first. Maybe it happens in the privacy of your bedroom, late at night. You start to explore your body and figure out what feels good. It can be a bit nerve - wracking but also exciting as you discover something new about yourself.
It is completely abnormal. Such behavior is not only unethical but can also lead to a lot of problems in friendships and relationships. If a friend is doing this, it indicates that they have a warped view of sexual boundaries and respect. It can make the person whose girlfriend is in the story feel violated and can also damage the trust within the friendship.
Some appropriate alternatives could be stories about friendship at a hen party. For example, tales of the bride-to -be and her friends sharing memories, playing innocent games like bridal bingo or charades, and having a great time chatting and laughing over a nice dinner.