Based on a movie under the same name.

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.

Chelsea was troubled by her boss's efforts to force her into a relationship. She couldn't find a diplomatic way to rebuff him, and she ended up going with him to a party held by Ryder-Gem, a jewelry company and one of their clients. When she saw Quinn, a man who lived in the same building as her, at the party, she came up with a bright idea. Quinn was known as a playboy, but she would make him pretend to be her fiancé, just for now! However, Quinn got carried away with the role and announced their fake engagement in grand style. The next day, Chelsea's world was turned upside down by a newspaper article announcing their engagement. Quinn was actually Ryder-Gem's CEO!

Flora had taken over the hotel that her late sister and her husband used to run, and spends her days struggling to take care of her sister's one-year-old son. One day, a gorgeous guest, Ivo, who looked out of place in a small hotel, showed up in the storm. He was so beautiful, he looked like he came right out of a painting! That night, as she nursed her crying baby, Ivo listened to her confession. But she didn't know that he was her brother-in-law, and that his goal was to bring the baby home as heir to a wealthy Italian family...