Responses
Orange Marmalade(webtoon), Orange (manga), Shigatsu wa Kimi no Uso, Koizora, and lovely complex are a few I can think of atm. Personally I recommend you going onto http://www.webtoons.com/en/ and read Orange Marmalade because by the end you will be tearing up for the MC
Any mangas that get you in the feels ╥﹏╥