Responses
I think the perspective is completely from Touma’s view and it was meant to confuse us when he signed as “Ichinose” but then after the wedding Taichi pulls up with a ring on his finger implying that the two of them eventually got married and Touma took Ichinose last name
It seemed like Touma went to Futaba's wedding while Taichi went to his friend Mon's wedding, but at Futaba's he signs in as "Ichinose", so either that means they genuinely got married (possibly via adoption), or the POV switches and the Futaba part is from Taichi's perspective.
I don't know how to read it