Power is a major theme. Two Lucifers would bring a lot of power into one story, and it can be about who has more power or how they use their power together.
In the world of 'lucifer meets lucifer fanfiction', a common plot could involve a clash of egos. When two such powerful and complex characters meet, there's bound to be conflict. Some stories may also explore a romantic or at least a deeply emotional connection between them, as they are essentially the same being in different forms, and this connection can be both fascinating and disturbing at the same time.
The costume in a novel usually referred to the clothes worn by the characters in the novel. It could be real clothes, fictional clothes, or clothes designed according to the plot of the novel.
The design and choice of clothing for a novel usually took into account the identity, personality, occupation, environment, and other factors of the character. Some novels might describe the character's clothing in detail so that readers could better understand the character's appearance and inner world. Other novels might pay more attention to the character's clothing style and decoration to show the character's personality and taste.
In a novel, clothing could also be used as a part of the plot. The color, material, style, and other elements of the clothing could hint at the development of the plot and the direction of the relationship between the characters. Therefore, clothing was a very important element in a novel. It could add rich color and imagination to the novel.
Lucifer can be a good comic depending on your preferences. If you enjoy dark and mythical themes, it's likely to appeal to you. The character development is strong, and the world-building is immersive.