All my stories have a fast or medium build-up. They are all backed up with a storyline.
Since my stories are all set in a different time period, I want to make readers feel that this is not happening in 2023. This opens the door to lots of details that can quickly add up and become too much, this "too much" will of course vary depending on who the reader is. It is a challenge that comes with writing historical stories.
Some attitudes from the characters may also put off some readers. My latest chapter (pending approval) features a 1953 girl next door whose great ambition is to become a good housewife. She's really like your grand-mother back when she was a teen. I think this girl is absolutely adorable and the story moves quite quickly into something delightfully sexual, but this one feature about her personality could be a deal breaker for many readers today.
My teenage characters in this story were born in the late 1930s and they are nothing like today's teens. I chose to depict this and to feature a character that reflected the majority of girls back then; this carries a risk.
I'm moving away from physical descriptions and more into what the characters are thinking and feeling, but at the same time, I want the reader to be aware that teen girls back then did not wear jeans torn off and the knees; they usually wore a skirt and saddle shoes with bobby socks. The hairstyles were also different; every little detail was. What I usually do is mix these descriptions with sexual elements.
Today's readers also usually prefer the female gaze. My current story is written with an "I" character who is a straight male. And sorry gals, but he loves watching girls!
That particular story is long-winded and the characters evolve, but there's sexual tension and kissing right from the start, and a very intense sex scene at the end of chapter one; to me, this is fast development before sex.