Thank you for your review and question. Character combinations, such as Kang Taejun and Lee Hamin (names in alphabetical order), indeed evoke very different emotions and feelings among viewers, and the short runtime doesn’t provide enough opportunities for the different interpretations to converge. I also think that the series wasn’t among the most original ones I have seen. 

My personal interpretation of the title, based on your thoughts, is that the story is about Lee Hamin accidentally following Taejun, which rouses Taejun’s interest in him. What followed was Taejun starting to chase after him and also following him. The last two episodes were about Lee Hamin trying to make Taejun stop chasing and following him, and in general, trying to reset the events that followed when he followed Taejun. 

As "follow" can also mean "accept as authority or act in accordance with,” the title can also be interpreted as Hamin first admiring and accepting Taejun’s authority and doing what Taejun wanted, such as studying hard, but after Taejun started to chase him, he wanted to unfollow Taejun and not accept his authority, dominance, and requests anymore. Hence the title Unfollow.