Teasing Master Takagi-san (Blu-ray)

Why did Takagi decide to start teasing Nishikata? Why did it take so long for him to realize that he liked her not-so-subtle attentions? It's hard to say, but it's clear that they were dancing around each other for quite a while before they could admit how they really felt. And now they're taking care of a little one together! Okay, it's a kitten, and it's just until they can find a new home for...