Yuumei VTuber no Ani Dakedo, Nazeka Ore ga Yuumei ni Natteita - Ch. 15 - Wine's Big Bros' Debut Stream - Start

[Me]

Do not blood related sibling can marry each other?
I know biologically it is okay, but dont know about law, well time to find out i guess.

My understanding, and I am not a japanese lawyer, is that in Japan it largely depends on the family registry. To oversimplify, "do you and your stepsibling share a last name?" is the barrier to overcome.

I have no idea how easy that is to change outside of "by getting married", and no desire to really dig into this.