Kimagure Datenshi 2

Madoka came to an island in the south. She was asked out by a group of guys on the beach late night, but she put them the cold shoulder. But her friend, Hikaru was taken as a hostage and the tables were turned.... They are imprisoned in a locked room. Desperately struggled to escape for, but a fearful monster appeared before them....

[Edited from DLsite English]