BDSM. Needles through the outer labia, then imaginative use of thread to pull everything tightly together. (They are not sewn together.) If the edges of the labia were first abraded, and they were left joined as in the photo, then they would grow together, producing a much more permanent example of infibulation. This would be a much more serious pussy mod, though acceptable if done to a consenting adult. (The more common FGM variety, done to young girls who do not and cannot consent in certain countries is an abomination and all who practice it should be locked up for a long time irrespective of claiming historical, cultural or religious reasons.)
Bearing in mind that I’m not a supporter of FGM in any way, I do think consensual infibulation and similar modifications are amazing and want to explore these more. Especially when I have a vagina.