The love between a brother and a sister who tortures and kills each other spreads all over the world.
After a period of age, they are not the most compatible people, but they are the most perfect lovers.
Ps:
"Don't fill it up with love, I'm afraid it will overflow."
"Then don't fill it up, so you don't have to waste the overflowing love."
"But, I'm afraid you won't love me."
"How could it be? My love cannot be exchanged for water, so don't worry."