One can focus on the emotional aspects. For example, describe the longing, the jealousy, and the deep connection between the characters. You can show how they support each other during tough times or how they grow together.
The story of Dunkirk evacuation can be considered intense. The Allied forces were surrounded by the German army on the beaches of Dunkirk. Against all odds, a large number of soldiers were evacuated by a flotilla of small boats, along with naval vessels. It was a race against time and a display of great courage and desperation in the face of a dire military situation.
There are many. For instance, 'The Cask of Amontillado' by Poe. In this story, a man named Montresor lures his so - called friend Fortunato into the catacombs under the pretense of tasting a rare wine. He then walls Fortunato up alive, which is extremely intense. 'Young Goodman Brown' by Nathaniel Hawthorne is also intense. Goodman Brown goes on a journey into the forest at night and experiences a dark encounter that makes him question his faith and the goodness of those around him.
In a gay cruising story, a young man went to a beach that was a popular cruising spot. He saw an older, more experienced man. They started a conversation near the shore. The older man shared his life experiences, and the young man was intrigued. They went for a long walk along the beach, and the connection between them became more and more intense as they shared their hopes and dreams.
Public spaces are meant for positive, educational and respectful conversations. Erotic stories are private and often inappropriate matter. They can make people uncomfortable and violate social norms.
In mainstream literature, intense sex stories are generally not considered appropriate. Mainstream literature aims to reach a wide audience, including children and those with conservative values. Such stories often involve explicit sexual content which goes against the moral and ethical norms of a general readership.
One scary intense story is about a haunted house. A family moved into an old mansion. Every night, they would hear strange scratching noises coming from the attic. One day, the youngest son went up there and saw a shadowy figure. He ran down in terror, and from that night on, the family could feel a cold presence following them around the house.