Onsoku Hishou Sonic Mercedes ~Futago Heroine Choukyou Shirei!~

The Ars Magna, an evil group, ravages around the world to get the Elemental Core, a secret treasure. However, there are two heroines who fight against them! They are twin sisters, Sonic Mercedes and Sonic Gisele. They transform themselves using the power of the Elemental Core and beat all their enemies up. One day, Max, the main character, and Tesla, his partner, are ordered to get the Elemental Core. "Get it within a week! If you fail, you'll lose your lives!" They don't know what to do, but they are given a homunculus called Mattel. Mattel has the Elemental Core inside his body and its battle power is higher than Mercedes and Gisele. Max successfully takes one of the twins hostage and tries to get the Elemental Core out of her. However, he can't make it. It is said that the Elemental Core belongs to people who have pure souls. "If that's true, I can get it out of her by dirtying her soul...."