Kanojo wo Mamoru 51 no Houhou守護她的51種方法; 彼女を守る51の方法; 51 Maneras de salvar a mi novia; 51 Ways to Protect Your Lover; 51 Ways to Save My Girlfriend; Kanojo o Mamoru 51 no Hōhō

From ANN: February 23rd, 20XX. Looking for a job in the famous TV station at Odaiba, college senior Jin Mishima attended the recruitment orientation. Not far away from the station, Nanako Okano, a gothic lolita trying to attend a concert, found out that her friends tricked her about the concert ticket because of jealousy. The two bumped into each other and "reunited" -- they were junior high classmates -- moments before an earthquake of Richter Scale 8.1 turned the island (the entire city, in fact) into ruins.