You have to admit that it is extremely rare and unheard of when a woman does approach a guy they doesn't know, and when they do more likely then not its for selfish reasons. In this case, Megumi did just that. She was attracted to Yamato's looks and nothing more. I felt quite a sense of relief when Yamato did turn her down. 

Sukitte Iinayo General Spoilers:

I admire Yamato a lot as a character. It takes a certain mindset and wisdom to look at women the way he does. He doesn't judge them by their looks alone, or by face value. He digs deeper to find out who they truly  are, their personalities and how beautiful they are on the inside. Really, this is the mentality anyone should have if they are trying to find their soul mate and life partner. Physical appearance on the outside is just a bonus. I certainly would go for someone with a personality that is a keeper, similar to the route Yamato has chosen. 

Love is intricate and works in mysterious ways. One thing for certain however: judging a book by its cover is setting yourself up for disappointment, as well as missed opportunities. 

Sukitte Iinayo Episodes