To answer the original question:
It looks like a medieval style marriage, Knight to Lady, as arranged by Mab, the knight's queen. Therefore, there won't be any latex, at least not until a heir is conceived, cementing the relationship between the two nations. That said, it'd be foolish to assume that Mab would let her knight - who she invested quite a few years in shaping, and who commands a significant amount of Winter power- become a slave to anyone (else), even an ally.
In Changes, Lea put the demon part of Susan an Martin to sleep. It's not much of a stretch to say that Mab could teach Harry a similar technique, or at least nudge him to obtain the knowledge for himself. This way they'd be able to consumate their marriage, and everybody wins.
I kinda like Lara and Harry as a match. They've always had a bit of chemistry.