Slice each nori sheets halfway up, to the center of the sheet.
In the first quadrant lay flat your lox. In the second square add your avocado. In the third lay out your red onions. And the last square, spread out your cream cheese and layer on the cucumber slices. Drizzle the avocado with Sriracha and kewpie mayo. Add sesame seeds throughout.
Fold the lox layer up and towards the avocado and repeat until you have a square.