4 Books: Miki Falls Series Set - Spring, Summer, Autumn, Winter (Miki Falls Manga Set Series, Vol. 1, 2, 3, 4)

I happen to know this author and in person, he is really funny. Miki Falls is an english language manga series created by Mark Crilley. The main character is Miki Yoshida, who is starting her senior year at Fukuyama High School, determined to make it her best year yet. Her plans hit a snag when she meets Hiro Sakurai, a Deliverer, a quasi-celestial being brought to the earth to try to preserve love, which is slowly dying out. Miki and Hiro will find that their relationship will get them in difficult situations on more than one occasion. Each book is written during a different season, spanning over one year.