Azazel's fashion
Azazel, the protagonist's heroine and the ultimate Marchant, has a fashion sense that is quite interesting even within the game's universe. She wears flawless makeup and luxurious clothes in a mix of green and gold. In some dimension of time, the protagonist may have been heavily inspired by her fashion sense.
With this in-game DLC skin, you can play as The Monarch (Phenix), a protagonist with Azazel's tastes. He wears gilt-rimmed glasses and favours green and gold coats. His flamboyant and unique appearance will baffle any intruders who find themselves in this dungeon - some will be in awe of his incredible appearance, while others will be terrified of this bespectacled man in strange attire.
Either way, it doesn't really matter, because they'll die. Have fun with the portrait in the story and the cool skins in in-game combat. It will make you love Azazel that little bit more.