-The most interesting feature of Bilibili—and the one most central to community—is bullet commentary. When you consume content on Bilibili, comments from fellow community members flash across your screen, time-stamped to when that user had that reaction. Only members of the community—those who passed that 100-question exam—can leave comments,... See more

-Bilibili is built around shared interests and purposefully builds friction into community. In order to join a community, users have to pass a 100-question exam. A representative question to join the Harry Potter community, for instance, is: “How many horcruxes does Voldemort have?” (Any self-respecting person should know the answer is seven.)

Communities can ensure they stay niche and engaged by creating friction to join. Access to Bilibili communities is difficult to achieve. Users need to pass a 100-question multiple choice test within 60 minutes.