Both shows are based around moving on from a betrayal and finding new love in the process. Art, either in music or writing, is a huge component of each of these shows and the passion for these mediums are clear in the actor's performances.
They both have a setting of romance between co workers. There is also love at first by one party, who then relentlessly pursues the love interest without paying heed to their personal boundaries (in a 'loving' way of course), because it's only stalking if the person is not attractive
Both are short length BLs in which one of the leads has somewhat retreated from the world after a painful past and the other lead opens up his world again. In both, a former boyfriend returns and causes problems.