"I will grant you a wish in exchange of what you treasure the most"
What about you just taking the life of my relatives and granting the wish anyway? Deal? 😈
So I'm a bit curious since in the first panel it suggests what happened in the past with him living with his demon sister, but the next panel says that "My sister is...a demon," implying that she is still with him in the present. There is no tragedy tag involved so I'm going to assume that they stay together for the rest of their lives, at least I hope they do.
If anyone has a different interpretation of what was said, I would welcome all opinions.
By imagining her in whatever ungodly abomination true form she has, it's not so sweet seeing a gigantic demonic goat licking my tongue as if sealing a contract with me. IMAGE THAT.