@yukiwa
the dude and touko are connected by destiny. Time and time again they reincarnate together, and are fated to encounter, since the beginning of times and to hold the other dear.
Bird, horse, cat. The animals always represent Touko, the girl. As for the boy, he can be anyone, but always a person. In all lifetimes, she has to watch as he falls in love with someone else, or is happy together with someone else. Until, she finally reincarnates as a woman, and he as a man, as he wished. But, in every lifetime, she has a curl (be it in the fur, or her hair) that delimits the time she has. When the curl disappears, she has no more, meaning, she dies.
He marries the restaurant girl, no because he falls in love with her, but because Touko died soon after the end of the story. That's what his sentence at the end mean.