Densen Uta

Anzu Natsuno, an ordinary student at an all-girls high school, is walking in the hallway when she is attracted by a mysterious melody coming from the auditorium. There, she finds her classmate Kana singing and, much to Anzu's shock, commits suicide right before her. A few days later, Anzu is approached by magazine columnist Riku Nagasei, who is investigating an urban legend about the Densen Uta, or the infectious song, that turns whoever sings it suicidal. In order to verify the urban legend, Riku convinces Anzu and her friends to sing the song, which they reluctantly agree. Soon after, one by one, the girls begin to kill themselves. (from wikipedia.org) The manga artists for the first volume were URAKAWA Masaru & URAKAWA Kaya. The second & third volumes were done by Takedakento.