Negai wo Kanaete Moraou to Akuma wo Shoukan Shita kedo, Kawaikatta node Kekkon Shimashita: Akuma no Niizuma

A weak mercenary adventurer named Theo Aspel constantly joins and is expelled from adventuring parties. To improve his strength, he successfully summons a long-unsought demon who promises to grant a wish. Upon meeting, Theo’s desire for power is replaced by unexpected feelings. The demon, after stating the cost of her magic, is surprised when Theo asks for marriage. She agrees, and they begin a life together that draws attention from those around them. Their story involves a young man and woman with a slightly risqué dynamic.