This is so formulaic that guessing his technical reason was easy even for me, to stop any further proposals, but I didn't guess he actually hates women. Although I can't help but wonder about that. His might simpy have a personality of a single track mind, so when he wants to concentrate on his swordsmanship, he doesn't need anything else to disturb him. However, if his mind changes, then also that "hate" would instantly change. That being said, this is shoujo genre, so it's unlikely the explanation is that straightforward. It all might be a clever scheme to attract a hard-working woman who isn't looking for romance but needs a financial way out for her family.