The World of the Married (2020)

Oh Young is a nameless actor who dreams of becoming a big movie star. Then one day, he makes his breakthrough with a film and becomes a star overnight. He discovers a new hidden world of fame, power, and pleasure, but inevitably all things have a dark side, which puts everyone around him in danger.

Both have sexual content. Affair. Secret meeting. Lust develop. Angry jealous spouse. What was the ending?

Yi Hwan is a former professional baseball player. He was involved in fixing games and lost everything. Gang boss Sang Ha runs a money lending business and a gambling location. He makes Yi Hwan work for him. Meanwhile, Yi Hwan falls for bar owner Yeon Soo.

cheating on wife, affair, love triangle, give the same vibe as The world of married and as VIP Kdrama as well

Both dramas revolve around cheating partners. In both dramas, female leads are very powerful.
In total the World of Married has a more coherent story and better endings

Infidelity. Inner struggle to stay in marriage and not happy or change for happiness. Sexual content. Seductive. Strong main lead with high profile career.

Aizawa Naoya is happily married to his colleague Natsuna but faces temptation to cheat on his wife when a new employee Tachibana Noa joins his branch and seduces him repeatedly with all sorts of antics. ~~ Adapted from the manga series "Anata Wa Watashi Ni Otosaretai" written by Miyaguchi Jun and illustrated by Umesuzu.

Three men, who look like winners in life, are in fact struggling with their own sufferings that they desperately strive to keep undisclosed - schizophrenia, sex addiction and infidelity. For these three childhood friends, the harder they try to get out of their agony, the more complicated and puzzled it gets.

The First Half of My Life tells the story of an affluent carefree housewife, Luo Zi Jun who is blindsided by her husband's betrayal. Faced with heartbreak, divorce and child custody issues, Luo Zi Jun develops the fortitude and strength to face the struggles of being a single parent as she enters the "real world." This drama depicts the story of a bittersweet yearning of love, understanding, and repentance. In my opinion, the impressive acting, character development, dialogue, and story equal, if not surpass The World of the Married.

-Both have strong female leads who are very competent in their careers
-Both deal with the aftermath of infidelity and getting revenge on a cheating partner, although She Would Never Know seems more focused on romance, where The World of the Married is more dark and focused on the revenge aspect
-Both involve possessive/obsessive male leads
-Both have workplace love interests

A husband works as a successful prosecutor and his future appears bright, but he gets arrested for corruption in a political scandal. His wife who worked as an attorney prior to their marriage, now resumes her career after a 13 year hiatus. She begins to find her true identity.

Mature protagonists (adults)
Infidelity of partners
Parents behaviour affects their childrens
Greed for connections to social elite, power and money

Everything seems perfect in the life of the successful family doctor and associate director, Ji Sun Woo. She lives happily in Gosan with her handsome husband Lee Tae Oh, whom she financially helped establish an entertainment company, and their teenage son, Joon Young. However, the perfect image of a happy, loving family life shatters when she discovers that her husband is having an affair, and even their mutual friends are helping him conceal it. Devastated by the betrayal, she sets on a path of seeking revenge and recollecting her broken self.

Hino Misaki, a full-time housewife, has given up on her dream of being a manga artist. Her husband, Toru, is a manga editor, and their son, Yuto, has a severe allergy. When she sees a flyer recruiting new manga artists, Misaki begins drawing at night. One day, after leaving Toru to watch over Yuto, Yuto dies after a severe allergic reaction. After the funeral, Misaki learns that Yuto died due to an allergy attack from muffins from Toru's affair partner. A woman who wished for small happiness, but after realizing her wish would not come true, chose the path of revenge

A love story affair with a bit different storyline & plot with mature sexual content but both is worth watching drama. If you like mature love affairs story I definitely recommend this drama.