Kim Choong Jae has issued an official apology after receiving criticism for his poor etiquette while attending SHINee member Key's recent 'KEYLAND' solo concert.

On the evening of February 3, the television personality, who also works as a graphic designer, was caught doing personal work on his tablet PC while the concert was going on. According to the reports, he was not concentrating on the performance and had spent roughly an hour-and-a-half drawing.

Those sitting around him during the show revealed the news online, saying that it was bad manners.

The next morning, Kim Choong Jae took to his personal Instagram to express an apology, stating: "I'm sorry to all of those who I caused discomfort to by drawing on my tablet PC while at Key's concert."

He then revealed that the project he was working on was actually for Key, and the two had intentions of meeting after the concert to go over his designs. Because of his tight schedule, he had been fitting in working on the project when he could.

"I realize that it wasn't proper concert-going manners," he conceded.

Meanwhile, Key's 'KEYLAND' concert series runs every weekend through February 17 at the SMTOWN COEX Artium.

Check out Kim Choong Jae's Instagram apology below.