it's the original version of the 2nd remake, Sattawat is a doctor whose mother has a gambling addictions, he marries Anusaya to pay for her mother's debts & Anusaya agrees to marry Wat to be able get rid off her uncle Chaya who is in love with her.

Similar plot with reversed roles. Male lead is a ceo have a one night stand with the inexperienced female lead results in pregnancy

On both dramas female lead is strong, career driven CEOs, both goes into contact marriage, on begin again female lead breaks up from the male lead & gives birth secretly

The story about a young man who can see spirits but he’s scared of the living & he figures out it has to do with his ex love

Male lead is a gay CEO and he’s been given some time, he possesses the body of a young girl, together they bring closure to his business

It’s a supernatural drama , a woman who has inherited exorcism abilities from her mother, is the owner of a company that specializes in selling haunted houses, both teams up to sell houses that are haunted by vengeful spirits and lingering ghosts.

female lead is able to see spirits, getting easily bothered by them and needs the help of the male lead to feel secure/protected

Both have lead seeing ghost elements, Eun Oh has the ability to see ghosts, so he's used to being bothered by many kinds of ghosts. As a result, he isn’t afraid of ghosts anymore.

Then Eun Oh meets a virgin ghost named Arang.

Joo Joong Won is the stingy and greedy CEO of Kingdom, a conglomerate that includes a major department store and hotel. He meets the gloomy Tae Gong Shil, who started seeing ghosts after an accident. Their lives take a new turn as they work together to deal with the terror and sadness brought about by the spirits, while delving into a kidnapping incident in Joong Won's past. And unknowingly, they fell in love with each other

a love triangle between spirits and humans woman who is able to see spirits after waking up from a 6-year long coma and Cha Gun Woo, a man who only believes in solid evidence. The two detectives come to understand each other as they try to help the spirits attached to objects at a lost-and-found center rest in peace.

The story of an exorcist college boy with the ability to see and hear ghosts. This is more teen drama

This is more teen drama, male lead is a an exorcist college boy with the ability to see and hear ghosts.