Recently, Dies irae ~Amantes amentes~ got released on Steam. The game is a visual novel is about mysterious ritual during World War II and a young man named Ren who got released from the hospital. Price is free to play for basic play. For each heroine scenario, DLC purchase is required. Current special 10% off release price for each DLC is $17.99 or ¥1978 for a limited time. For more details, check out the store page. Here's a trailer.