I love Harry Potter,i like art,and im bisexual

Why do people randomly ship Blaise Zabini from Harry Potter with Osamu Dazai from Bungo Stray Dogs?

For Harry Potter fans:https://pad.devloprog.org/p/Harry_Potter_rp

Pls let me know if you are joining the rp first,also p.s.If you see someone named Minori Tenichi that's me I am apart of an mha one