• The BTS Universe or Bangtan Universe (often shortened to BU) was initially known as The Most Beautiful Moment in Life Series (HYYH series) until the official name and logo were first used in 2017. It is a South Korean media franchise and shared fictional universe that is centered on a series of music videos and short films, independently produced by HYBE (formerly Big Hit) and based on characters inspired by the members of BTS. The franchise has expanded to include short stories, books, a webtoon, and visual novel. In the future, they plan to release a drama of the franchise.
• The BU is a very extensive storyline with BTS's music. If you'd like to learn more, you can find a link here: A Guide to the Bangtan Universe.

https://www.youtube.com/watch?v=EHdK5U2hf4o