what in hell is bad

Based on the search results, "What in Hell is Bad?" is a title of an adult otome game. It features the Seven Deadly Sins and up to 72 demons, allowing players to interact with them in various ways. The game is gacha-based and has interactive features like being able to touch the characters in all kinds of ways. The games story revolves around God disappearing one day, and all the blame is on Hell. Therefore, the phrase "What in Hell is Bad?" is not a common expression or idiom, but rather a title of a game.