Byul revealed how HaHa proposed to her on SBS's 'Strong Heart'.

She confessed that she was the first one to suggest that they get legally married. HaHa had been elated at her suggestion, and took her straight to the borough office to fill out marriage papers.

After they filled it out, one of the male workers suddenly gave her a bouquet of flowers. She said, "I thought it was an event that the borough office did. And then a worker pulled out a ring case. I wondered, 'is he our fan?' But then HaHa took the ring, and then HaHa's friends revealed themselves stating, 'Donghoon, congratulations on your marriage.' He'd prepared a surprise event for me. He proposed to me by saying, 'Become my last love'."

She showed off the ring HaHa had given her, boasting, "There's only one in the world. HaHa customized the design."