South Korean singer-actor Hwang Chansung announced Wednesday that he was getting married early next year, adding that his fiancé is pregnant and that he would be leaving his long-time agency JYP Entertainment.

The 31-year-old artist, who rose to fame as a member of the K-pop boy band 2PM, disclosed the developments in his personal life and career through a handwritten letter posted on his Instagram account.

"There is someone who I have been in a relationship with for a long time. This person has been the resting place for my unstable heart and a friend who I can share anything with for a long time, and she became my girlfriend," Chansung wrote in the letter that was translated to English by K-pop news outlet Soompi.

"While preparing and planning marriage with this person after my military discharge, the blessing of a new life came to us earlier than expected, and we are planning to get married as early as the beginning of next year," said the K-pop veteran, who was discharged from the military earlier this year.

Chansung said his partner "does not have the same job as me," appealing to fans to refrain from revealing her identity.

He also bared that he would be leaving JYP Entertainment, his talent agency for the past 15 years. His contract is set to expire in January.

"The company is my root and like an old friend, and we will always support each other’s growth," he said of JYP, one of the leading K-pop companies.

Chansung said he has yet to decide on his career path, "but I will share plans that won’t cause concern to fans."

The artist did not say if he would also leave 2PM but it was possible for him to stay in the group even if he signs with another talent agency, which was the case with member Ok Taecyeon.

Chansung debuted in 2008 with 2PM, which popularized the macho "beast idol" image in the K-pop scene. The group's hits include "Again & Again," "Heartbeat," and "My House."

In June, 2PM released the album "Must," the group's first record after a five-year hiatus due to the members' military service.

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Outside of K-pop, Chansung has also ventured into acting, starring in dramas such as "What's Wrong with Secretary Kim?" and "So I Married the Anti-fan."