Fam and Ihrie are willing to do almost anything to make a buck. So when these debt-driven damsels discover the potential profits to be hand in recovering a particularly dangerous mystical object, it means mortal peril for an entire civilization. There's no guarantee that they'll live long enough to squander the fabulous wealth they've been promised, and danger lurks around every turn as they cross dark seas in pursuit of legendary evil. Haunted by an unspeakable curse, plagued by doomsday prophecies, plotted against by untrustworthy traveling companions and looked in desperate race to gain the Ultimate Power, Fam and Ihrie are the Ruin Explorers!

Soon after entering middle school, Yuri Otani is coerced into joining the "Alien Party," a single-minded group with one goal: capture any alien attempting to enter school grounds. Terrified of aliens her entire life, Otani is anything but thrilled, and to make matters worse, her kit includes a "Borg"—an alien-like creature tasked with ensuring her safety. Despite this, she finds solace in her two partners: the independent and reliable Kumi Kawamura, and the smart and energetic Kasumi Tomine. As the Alien Party works to fend off extraterrestrial threats, will their roller blades and lacrosse sticks be enough to overcome the dire challenges ahead, or will they succumb to fear and suffer the grim consequences of defeat? [Written by MAL Rewrite]

OVA episodes bundled with the 8th and 11th volumes of the manga.

Ikkitousen OVA.