Fans of the popular K-pop boy group BTS think that Jin is dating based on what Jimin and RM say and do.
BTS recently had their FESTA Dinner Party, which is an event they do every year to celebrate their group's anniversary.
Members sit around, talk, and discuss about memories from the past. Here, Jimin and RM might have slipped up and said something that gave away Jin's relationship.
In particular, BTS's dorm contract has ended, so after 9 years of living together, the 7 members are now living on their own.
As RM talked about each new home, he suddenly said that Jin's place was a "newlywed house" that was "all white and bright."
But that wasn't the end of it. The way Jimin reacted to these descriptions is what led to rumors that Jin was dating Jimin.
When the word "newlywed" was said, the male idol laughed and covered his face. He even asked, "How much of all this can we air?" as if this was supposed to be a secret.
Soon, a clip of RM and Jimin went viral on the internet, and fans started analyzing Jimin's style and making guesses about Jin's supposed dating life and even plans to get married.
They also said that Jin wanted to get married when he was 31, but he is now 30. There are, of course, a lot of assumptions, which you should take with a grain of salt.
Source[1]