Excite Joutou!

From Shoujo Crusade: "I really want to become Rui’s protector!" Super introvert Souichirou frequently says this. However, whenever he listens to "Rocky"´s song, he immediately has a 180° change in his character (pervert)! Rui, who is always surrounded by guys who only care about a girl's figure and looks, wishes to meet a true prince one day, but sadly most are...? Would prevail love this time also...??!