In PSP game Akiba's Trip, you must strip vampires in broad daylight to expose them to the sun and kill them. PSP graphics are showing their age, which is why the illustrations in the game's complete guide provide a better glimpse at all the game has to offer—namely different kinds of underpants.
Akiba's Trip was released this past spring in Japan.
「AKIBA'S TRIP オフィシャルコンプリートガイド」描き下ろしイラスト＆小説も [アキバBlog]