Akai Tsuki: The Red Moon

ONE BOY HOLDS THE POWER TO DESTROY THE ENTIRE UNIVERSE IN HIS HANDS....

Summary
Bulma Briefs was haunted by a nightmare and tried to consult a well-known monk by the mountains during a camping trip. One night, she got lost in a rainy way and immediately made shelter into a nearby temple where she received a strange phone call from an unknown man with an irresistible, beautiful voice who ordered her to release the seven talisman seals in a certain jar, making him be freed from being sealed for five hundred years.
After Bulma released the seals, an unexpected sudden supernatural event happened as Vegeta, the known Legendary Destroyer of Worlds, was released from the seal. Scaring her, she ran away from the temple and got into an accident, where Vegeta saved her life by giving her his blood.

When Bulma woke up the next morning, she found a small boy sitting next to her, and claimed to saved her life. The boy also claimed (and keeps on claiming) that he is NOT a child neither human because he is a Saiyan and is over 500 years old! (But he looked like a five year old boy). Bulma thought the boy was joking around with her so she didn't believe at first. Believing the boy was lost, Bulma asked for the boy's name and parents. The boy responds that his name is Vegeta but he has no parents because they died a long, long time ago.

Later, just as Vegeta keeps on claiming he's an adult and not a human. Bulma thinks he's crazy so Vegeta swore to her that by the night of the Red Moon, he would find her and show her his true self and his True Powers, and by that same night, she shall die